A FRAMEWORK TO ASSESS BUG-BOUNTY PLATFORMS BASED ON
POTENTIAL ATTACK VECTORS
by
Susan Ann McCartney
A thesis submitted in partial fulfillment
of the requirements for the degree
of
Master of Science
in
Computer Science
MONTANA STATE UNIVERSITY
Bozeman, Montana
December 2022
©COPYRIGHT
by
Susan Ann McCartney
2022
All Rights Reserved
ii
DEDICATION
I dedicate this to my grandma Nancy, who inspired me to explore programs on the
computer at a young age and go into cybersecurity. She was also an inspiration by getting a
degree in computer science and programming in the early languages of Pascal, FORTRAN,
and Assembly.
I also dedicate this to my current fiancee and future husband, Spencer, who presented
me with the opportunity to program and helped me with classwork during the COVID-19
pandemic. He’s also pushed me to learn, grow, and stretch my knowledge by challenging my
ideas, from that I discovered the drive and determination I had to finish this paper.
I dedicate this to my parents, Tracy and Sandy, for always supporting me, emotionally
and financially, and ensuring that I received all the educational opportunities presented to
me.
iii
ACKNOWLEDGEMENTS
I would like acknowledge Chris Perkins and Jason Herbst from Medtronic for the
information on bug-bounty programs and platforms from a vendor’s perspective. Alex
Stevenson from Workiva for acting as the middle man to receive answers from BugCrowd
about the bug-bounty process. Reese Pearsall from Montana State University for assisting
in writing the malware sample script. Hoplite Industries for providing the malware sample
artifacts. The Department of Homeland Security for funding my research. Finally, I would
like to acknowledge Dr. Clemente Izurieta and Dr. Derek Reimanis for guiding me through
the research process and providing feedback on the design of my conceptual framework.
iv
TABLE OF CONTENTS
1. INTRODUCTION .................................................................................................. 1
2. BACKGROUND..................................................................................................... 3
Hackers.................................................................................................................. 3
Bug-Bounty............................................................................................................ 3
In-House Platform ...........................................................................................4
Third-Party Platforms ..................................................................................... 4
Program Management Process .........................................................................5
Standards and Regulations ...................................................................................... 7
Federal Risk and Authorization Management Program (FedRAMP) ...................7
National Institute of Standards and Technology (NIST) 800-53 .......................... 7
General Data Protection Regulations (GDPR) .................................................. 8
ISO/IEC 29147: Information Technology - Security Tech-
niques - Vulnerability Disclosure ................................................................ 8
ISO-27001....................................................................................................... 8
Bug Reports........................................................................................................... 9
Malware............................................................................................................... 10
Ransomware ................................................................................................. 10
Spyware........................................................................................................ 11
Adware......................................................................................................... 11
Trojan .......................................................................................................... 11
Worm ........................................................................................................... 12
Virus ............................................................................................................ 12
Script-Based Malware .................................................................................... 12
Stego Malware .............................................................................................. 12
PUA/PUP .................................................................................................... 13
3. MOTIVATION ..................................................................................................... 14
Security Frameworks............................................................................................. 15
UK National Cybersecurity Centre (NCSC) .................................................... 15
Cyber-Informed Engineering(CIE) .................................................................. 16
National Institute for Standards and Technology (NIST) Cy-
bersecurity Framework ............................................................................ 17
Tree for Cybersecurity Frameworks........................................................................ 17
Using the Connections .......................................................................................... 18
Interview Questions for Exploring the Security of the Platform................................ 19
Analyzing Malware Samples .................................................................................. 21
v
TABLE OF CONTENTS CONTINUED
4. GQM (GOAL, QUESTION, METRIC) .................................................................. 25
Goal 1 .......................................................................................................... 25
Goal 2 .......................................................................................................... 25
Questions...................................................................................................... 25
Metrics ......................................................................................................... 26
5. PROCESS ............................................................................................................ 27
Heuristics for Data Collection................................................................................ 27
Preliminary Guiding Questions....................................................................... 28
Data Collection Process ........................................................................................ 28
Registering for Different Platforms......................................................................... 31
File Attachments with Vulnerability Reports .......................................................... 33
Current Malware Detection Plans .......................................................................... 37
Differences in Platforms ........................................................................................ 37
Relation of Malware and File Types....................................................................... 38
6. ANALYSIS........................................................................................................... 40
Observational Case Study ..................................................................................... 40
Q1: Are there any standards and regulations implemented in the
platforms that prevent malware infection through a vulnerabil-
ity report?...................................................................................................... 44
Q2: Using the data collected, what file types are most commonly
used and what is the type of malware that corresponds with
that type? ...................................................................................................... 45
Q3: By illustrating the relationship between file extensions and
malware types, can this conceptual framework improve the
ability for vendors to assess the safety of bug reports?....................................... 45
7. CONCEPTUAL FRAMEWORK ........................................................................... 47
Components of the Conceptual Framework............................................................. 48
File Attachments........................................................................................... 48
Malware Types.............................................................................................. 49
Bug-Bounty Platforms ................................................................................... 49
Discussion ............................................................................................................ 50
ISO Modification Recommendation................................................................. 50
Hypothesis of Conceptual Framework ............................................................. 51
Justifying The Theory .......................................................................................... 52
vi
TABLE OF CONTENTS CONTINUED
Building the Theory.............................................................................................. 52
The Relationship Between Bug Report Attachments and Malware ........................... 55
How to use the Conceptual Framework .................................................................. 60
Conceptual Framework Use Cases.......................................................................... 60
8. CONCLUSION ..................................................................................................... 61
Future Work......................................................................................................... 61
Motivation and Contribution ................................................................................. 62
REFERENCES CITED.............................................................................................. 64
APPENDICES .......................................................................................................... 68
APPENDIX A : Bug Bounty Platform Tables ........................................................ 69
APPENDIX B : Malware Metadata....................................................................... 77
APPENDIX C : Malware/File Type Analysis Data ................................................ 81
APPENDIX D : Components of the Framework ..................................................... 84
vii
LIST OF TABLES
Table Page
3.1 Malware File Extensions Used in Study ...................................................... 21
5.1 Third-Party Platform Data Collection on Registration In-
formation, Geographical Location, Standard Compliance,
and Service Options for all Identified Platforms .......................................... 28
5.2 Selected Third-Party Platforms with Geographical, Stan-
dard Compliance, and Year Established...................................................... 31
5.3 Third-Party Platforms Report Attachment Restrictions on
Size and Count ......................................................................................... 34
5.4 Accepted File Types on Bug-Bounty Platforms ........................................... 35
6.1 Data Collection of File Extension and Count on Malware
Samples with More than 20 Samples per Extension ..................................... 41
6.2 Selected File Extensions with File Count and Category(Type) ..................... 42
6.3 Relationship between Types of Malware and File Extensions ....................... 43
7.1 The Correlation Between File Types and Compliance .................................. 49
A.1 Bug-Bounty Platform Resources................................................................. 75
viii
LIST OF FIGURES
Figure Page
2.1 The process through which researchers, vendors, and plat-
forms submit, manage, and maintain report submissions................................ 6
3.1 The Connections between NIST Cybersecurity Framework,
NCSC Secure Design Principles, and the CIE Framework [10] ...................... 18
4.1 Research Goals Questions Metrics for Building the Concep-
tual Framework......................................................................................... 26
7.1 Summary of Vulnerability Handling Process from ISO-29147[16] .................. 51
7.2 Structural: A UML Theory Diagram for the Effects of
Malware Analysis in Reports ..................................................................... 55
7.3 Structural: Map of Malware Types with Identified File
Types
................................................................................................................ 56
7.4 Structural: A UML Class Diagram Illustrating the Struc-
ture of the Framework
................................................................................................................ 57
7.5 Behavioral: Flowchart for Companies Using a Bug-Bounty
Platform to Assess Potential Attack Vectors ............................................... 59
ix
NOMENCLATURE
Definition 1.2.2: Bug-Bounty Platform
A third-party service that maintains a web interface for companies that wish to host a bug
bounty program.
Definition 1.2.1: Bug-Bounty Program
A strategy used by companies who wish to improve the security of their software or products
to deter hackers from exploiting their security vulnerabilities. There is a monetary benefit
for reporting security vulnerabilities.
Definition 7.0.1: Conceptual Framework
A framework that allows one to generate a theory based on the combination of other existing
theories or phenomena. A conceptual framework is used to explain the behavior when all
the components interact with each other.
Definition 3.2.1: Framework
A set of guidelines or requirements that a company should follow.
Definition 2.1.0: Hacker
A person who enjoys the intellectual challenge of over creatively overcoming limitations.
Definition 2.5.1: Malware
A script or file that is used to disrupt activity of cause mischief to the user.
Definition 1.2.6: Penetration Testing
Security testing used to identify any holes in the software system that could cause a
vulnerability exploitation.
Definition 1.2.3: Researcher
A white hat hacker who reports security vulnerabilities to the bug bounty program.
Definition 1.2.7: Red Teaming
The offensive security team that does penetration testing internally in the company.
Definition 1.2.4: Vendor
A company that hosts a bug bounty program on the platform.
Definition 1.2.5: Vulnerability Disclosure Policy
A policy that defines what vulnerabilities are considered valid based on scope and format.
x
ABSTRACT
Corporate computer security is becoming increasingly important because the frequency
and severity of cyberattacks on businesses is high and increasing. One way to improve the
security of company software is for a company to hire a third party to identify and report
vulnerabilities, blocks of code that can be exploited. A bug-bounty program incentivizes
ethical hackers (herein, ‘researchers’) to find and fix vulnerabilities before they can be
exploited. For this reason, bug-bounty programs have been increasing in popularity since
their inception a decade ago. However, the increase in their use and popularity also increases
the likelihood of the companies being targeted by malicious actors by using a bug-bounty
programs as the medium.
The literature review and investigation into the rules and requirements for bug-bounty
platform revealed that though the bug-bounty programs can improve a vendor’s security,
the programs still contain a serious security flaw. The platforms are not required to scan
reports for malware and there is no guidance requesting the vendors scan for malware. This
means it is possible to perform a cyberattack using malware as a report attachment.
Through data collection from 22 platforms, an observational case study, and analysis
of different malware, I have created a tool to assist vendors in selecting the platform
of best fit and characterize the possible attack surfaces presented from the file options
allowed on the platform. The outcome from this research is evidence of the importance
of understanding the malware files used as report attachments. However, more research
is needed in the relationship between file extensions and malware in order to thoroughly
comprehend the attack surface capabilities, and to understand the trade-offs between security
and convenience.
1
INTRODUCTION
Cybersecurity is becoming highly important because the frequency and severity of
attacks is increasing [40]. The popularity of exploiting vulnerabilities is increasing.
1
Exploits
and public disclosures of vulnerabilities have damaged companies’ reputations or, in some
cases, have caused companies to go out of business [26, 28].
In the past decade, the development of bug-bounty platforms has been used to help
improve security for practitioners. The platforms provide a cost alternative way for
vendors and practitioners to balance in-house and third-party security. The goal of a
bug-bounty program is to help the vendor find vulnerabilities and fix/patch them before
the vulnerabilities can be exploited. A Bug-Bounty Program is a strategy used by
companies who wish to improve the security of their software or products to deter hackers
from exploiting their security vulnerabilities. There is a monetary benefit for reporting
security vulnerabilities.
The use of a bug-bounty program benefits both hackers and companies. Bug-bounty
programs provide hackers with a legal way to find vulnerabilities and provide an incentive
to disclose their findings to the company. The benefit to a company is to allow them time to
fix the reported vulnerabilities with assurance that the vulnerability is not publicly disclosed
until the issue is resolved.
More companies are hosting a bug-bounty program on a platform to improve their
cybersecurity in an effort to maintain confidentiality of their customer’s data. A bug-bounty
platform is used to inform vendors of bugs in their software, leaving time for vendors to focus
on other company obligations. However, there is a security flaw with the platform: there is
1
CVE count by year
2
no requirement for protection or guidance for practitioners responsible for interpreting the
results from the bug-bounty program. This means there is no way to avoid successful attacks
through the vulnerability reports.
Therefore, the objective of this research is to create a tool for vendors to assist in
selecting the bug-bounty platform that best fits their needs. In addition, I want to assist
vendors in characterizing the landscape of attack surfaces through malware analysis and an
observational case study of a set of malware because malware types are platform dependent.
This paper is an illustration of the important concepts required for the tool, an outline
of the process for collected data and the results from the case study, and an analysis of the
components of the tool. Chapter Two defines the important concepts of the tool. Chapter
Three defines the purpose for each concept. Chapter Four describes the research goals and the
questions that align with the structure of the conceptual framework. Chapter Five describes
the data collection process using abduction and induction approaches. Chapter Six outlines
the observational case study, analyzes and determines the meaning of the collected data, and
determines how to portray the results from our research. Chapter Seven illustrates the tool
and demonstrates its use cases for assessing the potential attack surfaces. Finally, Chapter
Eight forms the conclusion of my findings and areas for future research.
3
BACKGROUND
There are three components to this framework. All have been thoroughly researched,
but these concepts have not been connected. This chapter creates the connections between
bug-bounty, files, and malware to help produce my final tool. There are several terms that
need illustration before I can identify and define the concepts.
Hackers
According to Ellis’s article on bug bounties [9], a hacker is defined as a person who
enjoys the intellectual challenge of creatively overcoming limitations. An ethical hacker or
(herein researcher) is the main type of hacker in this research. Researchers abide by the
law and obtain permission to hack, reporting their findings to the company - software owner.
The use of researchers provides an innovative, agile, and low-cost alternative to companies,
especially in relation to bug-bounty programs [9].
Not all hackers are good, some hackers have malicious intent and want to destroy
companies - to steal data and sell it for profit [13, 14]. The goal for these hackers, or black
hat hackers, is to disrupt availability, violate confidentiality, and compromise integrity. This
is accomplished by exploiting vulnerabilities. A vulnerability is a block of code or a piece
of software that is susceptible to unauthorized access.
There are companies in the cyber world that use the detection of vulnerabilities to make
a profit - the bug-bounty platforms, which connect researchers and companies to improve
corporate security for software.
Bug-Bounty
There are two types of bug-bounty platforms: in-house and third-party. The scope of
this research is on third-party platforms. The main purpose of the platform is to provide
4
services to companies and a channel of communication for researchers. Most of the services
provided for the bug-bounty programs is to validate
1
and triage
2
reported vulnerabilities.
Once the reports have been validated and triaged the vendor is notified that the reports are
ready for viewing. A vendor is the term used to label a company that hosts a bug-bounty
program on a platform.
In-House Platform
An in-house bug-bounty platform is handled internally by the company’s employees.
In order for companies to manage an in-house platform, the company needs to have the
resources to manage a bug-bounty program. These duties include validating, triaging, and
remediating all vulnerability submissions. Google, Microsoft, and Facebook all host their
own in-house platform, but use a third-party platform to handle the bounty payouts and
pool of researchers.
3
Third-Party Platforms
A third-party platform is a company that provides software as a service for companies
that want to improve their security at minimal cost and time [17]. Platforms have a range of
services available to vendors, from acting as the middle man between researcher and vendor
to filtering and sorting vulnerability submissions [24]. In exchange for use of the platform’s
services, the platform charges a fee for each bounty payout [3]. The third-party platform is
mainly used for filtering submissions by removing invalid or duplicate entries. These types
of submission make up a significant amount of all entries [20, 37, 38].
There are many bug-bounty programs that require researchers’ participation in order
to thrive and have a successful security program. The bug-bounty program gets its name
1
Remove reports that are not correctly formatted, are not in scope of the policy, have already been
reported, and have no relevance to the companies security.
2
Sort reports based on severity of reported vulnerability and level of impact of software availability.
3
https://bughunters.google.com/Google bug-bounty
5
because if a vulnerability is considered ‘valid,’ then the researcher receives a reward for
reporting the vulnerability. But rewards are not restricted to monetary benefits. Points and
swag can also be a reward [3, 18, 24]. A bug-bounty program is successful for a company
when there is a balance between utilizing in-house protection (i.e. security team) and the use
of a bug-bounty program [39]. Some company program options include run private, public,
and a mixture of public and private.
As a middle man, the platform ensures the researcher abides with the disclosure policy,
4
and assures that the researcher gets its reward for submitting a valid report [24]. The
platforms also validates and triages submissions using their own workers and contractors.
The contractors are employed by the platforms’ owning authority, some of whom are past
researchers who transitioned from writing reports to validating reports [9].
There are three different use cases for the platform. One use case is so researchers
can view the vulnerability disclosure policies, create and submit a bug report, and view all
the public programs and any private programs from invitation. Another use case is so the
vendors can update their vulnerability disclosure policy, view any submitted reports in their
program, and update the status of reports. The final use case is for the platform itself:
providing communication between vendor and researcher, updating the report once it has
been validated and triaged, and sending funds to the researcher.
Program Management Process
The process in which vulnerabilities are found and reported is depicted in Figure 2.1,
illustrating the interactions between vendors, platform, and researchers. The process is
initiated by the vendor with a request to host a program on the platform. Before the
4
In order for a bug-bounty program to be successful, a program must have rules and guidelines to
be followed by the hacker and the vendor to ensure clear and concise communication and remediation of
vulnerabilities. These rules and guidelines are written as the policy, and there is a standard policy established
in the ISO/IEC 29147 standard
6
platform will publicize the program and send a notification to the pool of researchers, the
platform requests the vendor send money to pay for future rewards and service fees.
The vendor sends a large sum of money to the platform and then the platform sends
a promotion email to all the researchers, requesting them to participate in the vendor’s
program and find vulnerabilities. When a researcher finds a vulnerability, they create a
report and submit it to the program. Then, the platform triages the report submission and
determines if it is valid. If the report is valid, then the submission is updated and the vendor
is notified that the report has been validated. It is then the responsibility of the vendor to
review the report and determine a plan to fix/patch the vulnerability.
Once a fix has been determined, the vendor approves the submission and notifies the
platform that the report is valid and tells the platform the reward amount for the found
vulnerability. The platform takes their service fee from the pool and sends the reward to the
researcher. Finally, the researcher receives their reward, and will continue looking for more
vulnerabilities.
Figure 2.1: The process through which researchers, vendors, and platforms submit, manage,
and maintain report submissions.
7
The platforms follow a set of standards that guide the platforms in managing bug-
bounty programs and handling vulnerabilities submitted to the program.
Standards and Regulations
The difference between each platform is standards and regulations of compliance. For
instance, HackerOne and BugCrowd comply to ISO/IEC 29147 and FedRAMP.
5
Because
both platforms have government customers, they have to follow U.S. federal regulations.
In the European Union, there is an all encompassing set of regulations called GDPR
6
used for any company that has to store or transfer customer information. Below is an in
depth explanation of relevant platforms.
Federal Risk and Authorization Management Program (FedRAMP)
FedRAMP is a standard required by any company that has a government organization
as a customer and is only required in the United States. Companies from other countries
that have U.S. government organizations as customers are also required to comply with
FedRAMP. This standard ensures there is a plan in case of data breaches or other
emergencies, and problems are solved in a timely manner. It also requires a continuous
monitoring system to ensure that the necessary data is encrypted and not easily accessible
to unauthorized actors.
National Institute of Standards and Technology (NIST) 800-53
FedRAMP uses NIST 800-53
7
as a baseline for their procedures and requirements.
NIST 800-53 provides a catalog of security and privacy controls for information systems
5
Federal Risk and Authorization Management Program
6
General Data Protection Regulations
7
National Institute of Standards and Technology standard 800-53 revision 5
8
and organizations to protect operations and assets.
8
These controls are flexible and can be
adapted for any use.
General Data Protection Regulations (GDPR)
The E.U. GDPR focuses on the compliance of securing and transferring personal data
and provides flexibility in how rules are used by companies. Certification of GDPR lasts for
three years and can be withdrawn if requirements are not met during assessments [33].
ISO/IEC 29147: Information Technology - Security Techniques - Vulnerability Disclosure
This standard defines the reporting format used by every platform. However, not every
platform complies with this standard. ISO-29147 is the guide on how to manage a program
and format the reports. This standard pairs with ISO-30111 which explains how to receive
vulnerability reports and process them.
The platforms use a tracking system to categorize report submissions as blocked, new,
triage, resolved, or valid. While traditionally, the platform will triage the submissions for a
vendor, a vendor’s employees can still view the reports before the platform has reviewed the
submissions. The reports are not encrypted on the platform, so all that is required to read
and exploit vulnerabilities is a single sign-on.
ISO-27001
This standard, also known as the ISMS
9
standard, contains four phases of compliance:
risk assessment, information security planning, security testing and evaluation, and certi-
fication and accreditation. This is the most popular ISO standard because compliance to
this standard ensures the security of the organization’s data and resources by implementing
effective, time-verified security controls [15].
8
https://csrc.nist.gov/publications/detail/sp/800-53/rev-5/final
9
Information Security Management System
9
Bug Reports
Bug reports (or vulnerability reports) are created by researchers to help vendors improve
the security of their products and services. The report is considered ‘valid’ if it is within the
scope of the program policy, follows the reporting format, and has not been reported before.
Every platform adheres to a format for vulnerability reports as described in the ISO-29147
standards, with the major variation coming from the attachments in a report [16].
A bug-bounty report can contain:
product or service name, URL, or affected version information;
operating system of involved components;
version information;
technical description of actions being performed;
sample code that was used to test or demonstrate the vulnerability;
reporter’s contact information;
other parties involved;
disclosure plan;
threat/risk assessment details of identified threats and/or risks including a risk level
for assessment results;
software configuration of the computer or device configuration at the time of discovering
the vulnerability;
relevant information about connected components and devices if a vulnerability arises
during interaction when a secondary component or device triggers the vulnerability;
time and date of discovery; and
browser information including type and version information [16].
The content of the report is significant because it can contain ‘sample code’ that
demonstrates the vulnerability. However, this content option can be used to attach malware
10
to the report, opening up the vendors on the platform to an attack vector that is not
referenced in any of the platforms, literature review, or standards and regulations complied
with by the platforms.
Malware
Malware has more than one type of attack vector, it contains several options. Malware,
or malicious software, is a file or script that is used to disrupt activity or cause mischief to
the user [25]. There are nine different types of malware (there are more types of malware,
but they are classified as subsets of the malware for this research.) It is important to provide
the differences of each type of malware to illustrate the potential attack vectors.
Ransomware
Ransomware is malware that encrypts a victim’s data or disables the functionality of
the victim’s computers until a payment is made to the attacker. A message may pop up
on the screen that states “you have browsed illicit materials and must pay a fine,” or the
message may be in a foreign language or from a foreign police force [22]. If the payment
is made, the victim receives a decryption key to restore access to their files. If the victim
refuses to pay the ransom, then the hacker publishes the data on data leak sites (DLS) or
blocks access to the files in perpetuity.
10
Ransomware can be detected by monitoring for file entropy (file randomness). A file’s
entropy refers to a specific measure of randomness called ”Shannon Entropy,” where typical
text files will have a lower entropy and encrypted or compressed files will have a higher
entropy. In other words, by tracking files’ data change rate, one can determine whether the
file was encrypted or not.
11
10
https://www.crowdstrike.com/cybersecurity-101/malware/malware-vs-virus/
11
Ransomware Detection Techniques
11
Spyware
Spyware is malware that attempts to silently monitor the behavior of users, record
their web-surfing habits, or steal their sensitive data (i.e. passwords, personal identification
numbers (PINs), and payment information) [2, 8]. The information is then sent to
advertisers, data collection firms, or malicious third-parties for a profit.
12
Spyware tends
to make a victim’s computer sluggish and slow to respond. The best way to monitor for
spyware is to test the computer’s performance.
Adware
Adware is an automated, unwanted software designed to bombard users with advertise-
ments, banners and pop-ups.
13
It infects a victim’s computer using downloadable content
deceptively enticing to victims. Adware makes advertisements appear in places where they
normally would not. Monitoring for excessive appearances of advertisements is an effective
way to detect adware.
Trojan
A Trojan is a digital attack that disguises itself as desirable code or software. Trojans
may hide in games, applications, or even software patches. They may also be embedded
attachments in phishing emails. By using some form of social engineering to trick the user
into downloading the content, Trojans can take control of a victim’s systems for malicious
purposes such as deleting files, encrypting files, or sharing sensitive information with other
parties [12].
14
A Trojan has several attack surfaces, and one way to detect the presence of
a Trojan is by monitoring file activity. Files that are exported, modified, deleted, or altered
when not authorized is a sign that a Trojan is present on the computer.
12
https://www.crowdstrike.com/cybersecurity-101/what-is-spyware/
13
https://www.crowdstrike.com/cybersecurity-101/adware/
14
https://www.crowdstrike.com/cybersecurity-101/malware/trojans/
12
Worm
A computer worm is malware that attaches to a vulnerability host to replicate itself on
that computer and continuously searches another vulnerability host which can be replicated
onto another computer within the same network [11]. Typically, a worm spreads across a
network through an Internet or LAN (Local Area Network) connection.
15
Computer worms
are some of the oldest kinds of malware and can make a computer freeze or crash. Some
ways to detect the presence of a worm is by monitoring for unusual computer or internet
browser performance, and applications opening and running automatically.
Virus
A computer virus is a viral set that contains one program that reproduces itself [6]. Its
definition is limited only to programs or code that self-replicates or copies itself in order to
spread to other devices or areas of the network.
16
A virus will slow system performance,
delay computer restart and shutdown, increase system crashes and pop-up of error messages.
Script-Based Malware
Malware is written as a script within a file that performs malicious actions. Script-based
malware is most commonly used for web pages and documents in JavaScript [7].
Stego Malware
Stego malware, or stegware, is information hiding malware that uses Digital Stenogra-
phy
17
to avoid detection [32]. Stego malware can be detected by monitoring for unauthorized
uses of obfuscation. Obfuscation is the act of obscuring the file contents so they are not
intelligible.
15
https://www.malwarebytes.com/computer-worm
16
https://www.crowdstrike.com/cybersecurity-101/malware/malware-vs-virus/
17
Digital Stenography refers to the collection of techniques for hiding secret data inside innocuous looking
digital media.
13
PUA/PUP
Potential Unwanted Applications, or Potential Unwanted Programs is a piece of software
that is an option attached to free software downloads, or bundling software downloads. They
may also appear as pop-ups and unwanted advertisements. PUA/PUP can be detected by
monitoring the behavior of installed applications or programs for suspicious activity [19].
PUA and PUP are not classified as malware, but can be malicious just like malware.
14
MOTIVATION
This research focuses on characterizing attack vectors for bug-bounty programs because
of the nature of bug-bounty platforms: a third-party company that offers a service for
managing the vulnerabilities of other companies. These vulnerabilities are submitted in
reports that consist of file attachments. Given the fact that the platforms and current set of
standards do not mention ‘malware detection’, there is a necessity for improving the security
of maintaining bug-bounty programs for vendors.
The motivation for looking into the security of bug reports is because they are under
studied and there is no research looking into the relationship between file extensions and
malware. This relationship is important with bug-bounty programs because of the potential
for the disclosure of other vulnerabilities within the same program.
The reason for building a framework to characterize the attack vectors is because every
outcome from the framework can be different for each vendor. Therefore, a conceptual
framework is the best choice because of its flexibility in design and use.
Malware and bug bounty have been studied extensively, but the two have not been
connected. I use a conceptual framework to connect files and malware by using the report’s
file attachments as malware files. The framework will characterize the potential attack
vectors of malware allowed as a file attachment in a report. The best way to do just that is by
using a conceptual framework. Chapter Six explains more about the conceptual framework.
Because the standard and regulations used by the platforms do not contain any
suggestions for the safety of bug reports, I needed to find a security guide that would help
to understand what security frameworks existed and what made them successful. How can
I provide guidance to vendors without simply saying ‘do not trust third party services’ or
‘make sure to use malware detection?’
15
Security Frameworks
The security gap in the platforms is due to the lack of malware detection for bug reports.
There are a few cybersecurity frameworks that can address the security gap. The following
frameworks are not used by platforms, but are a good starting point to address the gap in
security. The three security frameworks to consider are NCSC, CIE, and NIST, all of which
have overlapping security guidelines.
UK National Cybersecurity Centre (NCSC)
The NCSC
1
is a security framework established during 2008 in the U.K. for clients and
customers that want the assurance that the data hosted by companies is secure. The NCSC
is a popular framework used in like-minded countries, not just in the U.K [31].
2
The NCSC
has also been established in the Netherlands and New Zealand [30, 35]. There are five secure
design principles used in the NCSC framework; the following is a summary for each principle
from the NCSC [21]:
1. Establishing the context: There is an understanding of the system operations and
designs, use of third-party services and tools, and potential risks. There is a clause in
this rule that specifically states that third-party services should not be fully trusted
because an attacker can access a company’s environment by gaining access through a
third-party service environment.
2. Making compromise difficult: A secure system is characterized by applying methods
and using techniques that make it harder for an attacker to compromise a company’s
system. The best way a company can protect itself from a security breach is by
transformation
3
, validation
4
, and safe rendering.
5
3. Making disruption difficult: Minimize access to certain interfaces to only those
necessary. Privileged access is be done on a device that does not view messages or
browse the internet. Monitor for security advisories and patches that need attention.
1
National Cybersecurity Centre
2
https://securityscorecard.com/blog/top-cybersecurity-frameworks-to-consider
3
Transformation is taking one file format and transforming the file into a trusted format.
4
Validation is checking to see if file and data structure are as expected for simple file formats
5
Safe rendering means using a a virtual environment
16
4. Making compromise detection easier: Ensure that the system and services are available
and functional.
5. Reducing the impact of compromise: Use a virus protection software and monitor for
suspicious activity.
Cyber-Informed Engineering(CIE)
The CIE was developed by INL
6
to develop security solutions for an industrial
application (more specifically, for nuclear and radioactive material facilities). There are
eleven elements that make up the CIE framework [1]:
1. Consequence/Impact Analysis: Ways to impact availability or to steal data.
2. System Architecture: Data flow in the system.
3. Engineered Controls: Controls to mitigate cyber vulnerabilities.
4. Design Simplification: Reduce the complexity of digital design to the bare minimum
that is absolutely necessary for critical functions.
5. Resilience Planning: Contingency planning and hardening of specific components or
systems is necessary.
6. Engineering Information Control: Protect specific engineering records that are
considered sensitive information (requirements, specifications, designs, configurations,
analysis, and testing during system operation).
7. Procurement and Contracting: Outside vendors are held responsible for strong
cybersecurity and collectively considered as part of the overall organizational cyber
defensive posture.
8. Interdependencies: The system owner plans for risks introduced by the support of
many disciplines, and understands the cybersecurity aspects of the interconnections.
9. Cybersecurity Culture: Cybersecurity is treated with the same rigor and attention as
physical protection security.
10. Digital Asset Inventory: A complete inventory of the hardware, firmware, and
software version levels of all engineering systems within the organization. Providing a
mechanism for organizations to track and analyze these and the vulnerabilities residing
in the software and hardware.
6
Idaho National Laboratory
17
11. Active Defense: Resilient dynamic strategies and enhanced technical skill competencies
to combat directed persistent attacks utilizing human behavior, supply chain, and state
of the art technology.
National Institute for Standards and Technology (NIST) Cybersecurity Framework
This framework uses the word ‘functions’ instead of using the word ‘principles.’
7
There
are five functions in this framework:
1. Identify: An organization understands and manages the potential risks to data,
systems, people, and assets.
2. Protect: Ensure data transfers and deliveries are secure.
3. Detect: Implement the necessary strategies and tools to monitor for suspicious activity.
4. Respond: Develop and implement remediation procedures to prevent cybersecurity
events.
5. Recover: Back up any data in the event of a cybersecurity incident.
Within each function there are a set of categories that provide a more in depth
coverage for each function. Each category has a unique identifier that provides a list of
the characteristics of each function.
Tree for Cybersecurity Frameworks
The principles for NCSC, CIE, and NIST connect together as depicted in Figure 3.1.
The framework for NIST and NCSC are activities to provide cybersecurity to a company,
and the CIE framework acts as artifacts that connect with the activities.
7
https://nvlpubs.nist.gov/nistpubs/CSWP/NIST.CSWP.04162018.pdf
18
Figure 3.1: The Connections between NIST Cybersecurity Framework, NCSC Secure Design
Principles, and the CIE Framework [10]
The NIST framework at the top carries down to the NCSC framework both of which
represent activities to promote security. The final level, the CIE framework, is the artifacts
that align with the activities that promote security. Four artifacts align with multiple
activities and each activity consists of more than one security artifact.
Using the Connections
In each framework, there’s at least one element that possesses the ability to provide
protection to the host of a bug-bounty program. Within the NIST Cybersecurity Framework,
we focus on the identity function; within the NCSC principle, we focus on ‘establishing
the context before designing a system’; and within the CIE framework, we focus on
interdependencies, engineering information control, and engineered controls. The focus on
these activities and artifacts align with the concept of malware detection for third-party
service outputs. By understanding the potential attack vectors in the attachments of bug
19
reports, the vendors can create procedures for cautiously downloading and reading reports
to avoid malware exposure.
Next, it was important to understand what tasks the platform provides for the vendor
before being notified by the platform of a new report submission. Since these questions came
from academia and not a customer, the questions were ignored. For that reason I requested
assistance from vendors to get answers. From the help of both Medtronic and Workiva, I
was able to perform an indirect interview and get an answer to these questions.
Interview Questions for Exploring the Security of the Platform
Post literature review, there were several questions whose answers were not immediately
available on the platforms’ websites. These questions are in the perspective of a company
enquiry of hosting a bug-bounty program with the platform BugCrowd:
Q1: Once a researcher submits a report, what’s the procedure for sending the report
to the vendor?
Q2: Before notifying the vendor, who or what views the report? Is there use of a
virtual environment to download or view the report?
Q3: Is malware detection part of the report validation process?
BugCrowd’s
8
response to the first question is similar to information that is found in
two of their own articles [4, 5]: using diagrams to show the process of how reports get to
the vendor. There is a team on the platform that ensures a report is valid (in scope of the
program policy, reproducible, not a duplicate of a previous report, and poses a security risk).
Once verified, they notify the vendor of the submission.
8
A third-party company located in the United States.
20
This leads to the second question, before notifying the vendor, who or what views
the report, and is there use of a virtual environment of some sort? The vendor’s side of
the platform can track the status of each report: new, blocked, valid, triaged, and done.
9
Therefore, this proves there is a potential to open a report with a status of ‘new’ before the
platform has a chance to validate it. For this reason, the vendor must be required to follow
a set of standards related to viewing the reports to stay secure; which there is no standard
that contains requirements for malware detection (and there is no known reason why there is
no malware detection in the standards). This response provides information for approaching
the design of our conceptual framework.
From the platform’s side of processing reports, the response from BugCrowd indicates
that each submission is triaged and validated by a member of the triage team before it is
sent to the vendor. This prevents the vendor from receiving non-valid (invalid, duplicate or
non-applicable) reports. There is not an order for triaging and validating, but there is an
indication that the ASE (Application Security Engineering) team uses a virtual environment
to triage the reports. The use of a VM
10
during triage may prevent malware infections, but
a platform’s computer would not avoid malicious bug reports in the validation process.
Since there is no use of a virtual environment for report validation, is there any malware
detection in the platform’s procedure? BugCrowd avoided answering this question, creating
the assumption that the platform does not scan reports for malware. This answer, or lack
there of, leads to a followup question. Even if platforms did scan reports for malware, how
does one scan for any malware when there are different types of file attachments in reports?
The analyzing of malware samples is needed to understand the relationship between malware
and file extensions, and to answer this question.
9
‘New’: has not been processed by the platform. ‘Blocked’: has an obstacle in the way that blocks a
solution. ‘Triaged’: platform has processed the report and a ticket has been created for the vendor. ‘Done’:
report has been fixed or patched.
10
Virtual Machine
21
Because the third question was not answered, the assumption that malware detection
is not done by the platform is acceptable. Therefore, an analysis of the relationship
between malware and file extensions is necessary before an investigation into the allowed
file attachments is done.
The data set of malware was gathered and sent by Hoplite Industries in three different
ways. First the samples were gathered by downloading data from VirusTotal, a malware
database that combines the file results from several malware detection companies. Hoplite
also set up some honeypots to lure in malware samples. And third, the malware was collected
from Hoplite’s security connections. From this set of data, a script was written to categorize
and move a smaller sample of malware data into a spreadsheet.
Analyzing Malware Samples
From looking at over 35 million different malware samples, a hypothesis was developed
consisting of the types of malware that would be used as attachments in bug reports. Later,
Chapter Five - Process - explains the correlation between the types of malware and file
extensions that have been used in each type of malware.
Using a malware sample size of 15,734, I determined the relationship between malware
and file extensions.
Table 3.1: Malware File Extensions Used in Study
Extension File Description
(no extension) Linux-Dev86 executable headerless
asm assembler source ASCII text
asm assembler source Non-ISO extended-ASCII text
asf Microsoft ASF
Continues on next page
22
Extension File Description
c C source ASCII text
com COM executable for DOS
com COM executable for MS-DOS
dat data
dex Dalvik dex file version 035
dll PE32 executable (DLL) (console) Intel 80386
dll PE32 executable (DLL) (GUI) Intel 80386 for MS Windows
dll PE32 executable (DLL) (native) Intel 80386 for MS Windows
dll PE32+ executable (DLL) (GUI) x86-64 for MS Windows
doc Composite Document File V2 Document Can’t read SSAT
doc Composite Document File V2 Document Little Endian Os
dos DOS batch file ASCII text with CRLF line terminators
dos DOS batch file ISO-8859 text
dos DOS executable (COM)
elf ELF 32-bit LSB executable Intel 80386 version 1 (SYSV)
exe PE32 executable (console) Intel 80386 for MS Windows
exe PE32 executable (GUI) Intel 80386 for MS Windows
exe PE32 executable (native) Intel 80386 for MS Windows
exe PE32 executable Intel 80386 for MS Windows
exe PE32+ executable (GUI) x86-64 for MS Windows
gif GIF image data version 89a 10 x 12
gz gzip compressed data from NTFS filesystem (NT)
gz gzip compressed data from Unix
Continues on next page
23
Extension File Description
html HTML document ASCII text
html HTML document ISO-8859 text
html HTML document Non-ISO extended-ASCII text
html HTML document UTF-8 Unicode (with BOM)
img DOS/MBR boot sector code offset 0x3c+2 OEM-ID ”MSDOS5.0”
iso ISO-8859 text with CRLF line terminators
iso Non-ISO extended-ASCII text
jar Java archive data (JAR)
java compiled Java class data
jpg JPEG image data JFIF standard 1.01 aspect ratio density 1x1
ms MS Windows shortcut Item
pas Pascal source ASCII text
pdf PDF document version 1.3
php PHP script ASCII text with CR line terminators
pl perl script ASCII text executable
pl perl script executable (binary data)
png PNG image data 8-bit/color RGBA non-interlaced
rar RAR archive data
rtf Rich Text Format
smgl exported SGML document ASCII text
smtp SMTP mail ASCII text with CRLF line terminators
swf Macromedia Flash data (compressed)
txt ASCII text
Continues on next page
24
Extension File Description
txt UTF-8 Unicode text
xls Composite Document File V2 Document Little Endian Os 0
xml XML document text
zip Zip archive data
The types of malware chosen are based on the findings in Table 3.1 - Adware,
Ransomware, Spyware, PUA/PUP, script-based malware, Trojan, Virus, Worm, and Stego
malware. Though Chapter Two defines the selected types of malware, this table supports
the reason why this set of malware was chosen. All will make sense in Chapter Six when
depicting the relationship between file extensions and malware, but at this point, know that
the malware was chosen based on the behavior of each malware type and the file extensions
used for that type.
The other reason this set of malware was chosen is because their initial attack vectors
are unique from each other, however malware of one type can be used to download and
spread malware of another type. Also, some malware types are subsets of another type, for
instance, a Trojan has several subsets like clickjack, exploits, and packers as will be shown in
Chapter Seven. Finally although PUA/PUP is not technically defined as a malware, there
is malware the is represented as PUA/PUP, like grayware.
25
GQM (GOAL, QUESTION, METRIC)
Following Soligen’s 2002 GQM [34]
1
, the aim is to achieve the goal by answering a set
of questions following a specific set of metrics. These metrics help answer questions, which
in turn helps accomplish the goal of this research. The specific goals, questions, and metrics
of this research are presented below:
Goal 1
Investigate bug-bounty programs for the purpose of providing a conceptual framework
with respect to malware detection in vulnerability reports from the perspective of reviewing
reports in the context of verifying no malicious attachments exist in the reports.
Goal 2
Investigate malware for the purpose of finding its relationship with file extensions with
respect to the file attachments allowed by a bug-bounty platform from the perspective of a
vendor(current or prospective) in the context of characterizing potential attack vectors.
Questions
Q1: Are there any standards and regulations implemented in the platforms that prevent
malware infection through a vulnerability report?
Q2: Using the data collected, what file types are most commonly used for the platforms
and what is the type of malware that corresponds with that file type?
Q3: By illustrating the relationship between file extensions and malware types, can the
conceptual framework improve the ability for vendors to assess the safety of vulnerability
reports?
1
Goals, Questions, Metrics
26
Answering these questions determines if there is a way to improve upon the current
security process in bug-bounty programs.
Metrics
M1: Malware Type (Q1, Q2, and Q3)
M2: Standards and Regulations (Q1)
A: ISO Standards, B: FedRAMP, C: GDPR
M3: File Type (Q2)
M4: Number of Platforms (Q1)
Figure 4.1: Research Goals Questions Metrics for Building the Conceptual Framework
27
PROCESS
This chapter provides the procedure used to collect all the platform data and portray
that data in tables. The research process uses inductive, abductive, and deductive
approaches. Abduction is defined as making a conclusion from what is known;, induction is
making an inference from an observation of the data.
1
The abductive portion of this research
is done using the literature review and the interview from a bug-bounty vendor, helping to
establish the knowledge necessary for the collection of data. The inductive portion of this
research is done by surveying each bug-bounty platform, which helps form the GQM (Goals
Questions Metrics). The GQM is used as an approach to analyze and refine the theory of this
conceptual framework using the deductive approach. A conceptual framework is assembled
using the results from this data collection and analysis.
The following information was gathered from each platform: services, geographical
location, standard compliance, registration information on researchers, year established, file
size and count, and file type restrictions. After gathering this data, it was reduced and
categorized for the study. The goal of the data collection was to gather enough information
to build the conceptual framework and understand the relationship between malware and
file extensions.
Heuristics for Data Collection
With the background knowledge acquired, careful and thoughtful research questions
were created that assist in identifying components in this observational study [36]. These
questions follow an inductive approach that helps determines the data to collect in the
investigation.
1
Merriam Webster Dictionary Definition
28
Preliminary Guiding Questions
PQ1: Is there a malware detection procedure for bug-bounty programs?
PQ2: Are there differences between platforms located in the U.S. and other countries?
PQ3: Are there types of files that malware can be attached to in a report?
Data Collection Process
The investigation began by exploring each platform and collecting data from its own
bug-bounty program as the sample. To aid the selection of platforms, a repository on GitHub
was used to provide a list of different bug-bounty platforms used around the world.
2
Also,
a Google search of different bug-bounty platforms was performed to create a final list of all
the platforms. Table 5.1 identifies the geographical location of the platform, their advertised
compliance to specific standards and regulations, the required information to register as a
researcher, and the service options available. The following list of abbreviations is used in
the table:
BB: Bug-Bounty Program
VD: Vulnerability Disclosure Program
PT: Penetration Testing
RT: Red Teaming
DoB: Date of Birth
Basics: First and Last Name, Username, and Email
Table 5.1: Third-Party Platform Data Collection on Registration Information, Geographical
Location, Standard Compliance, and Service Options for all Identified Platforms
2
https://github.com/disclose/bug-bounty-platforms
29
Platforms Location Stnds/Regs Personal Info Services
Antihack.me Singapore N/A N/A BB, PT, RT
BB Caribbean Caribbean ISO-27001 Application BB
BB Switzerland Switzerland GDPR Application BB
BugHunt Brazil None Basics BB, VD
BugBase India ISO-27001 Country of BB, PT, VD
Origin
BugBounter Turkey GDPR Basics BB
bugbounty.jp Japan ISO-29147 Basics BB
bugbounty.sa Saudi Arabia N/A Bank Account, BB
Tele #
bugbounty.ru Russia ISO-27001 Basics BB
BugCrowd US FedRAMP Basics BB, VD
Bugv Nepal None Basics BB, PT, VD
CrowdSwarm UAE N/A DoB, Tele #, BB, PT
Addr, Passport
Cyber Army Indonesia N/A Indonesia BB, VD
Indonesia Citizenship
Cyscope Chile None Country BB
Detectify Sweden GDPR TBD VD
EpicBounties Spain/LATAM GDPR DoB, Addr BB
Passport
Federacy US SOC2 Basics BB, PT, VD
FindBug Kosovo GDPR Complete CTF BB, VD
Continues on next page
30
Platforms Location Stnds/Regs Personal Info Services
Frontal UAE N/A Application BB, PT, VD
GObugfree Switzerland GDPR Basics BB, PT
HackenProof Estonia GDPR Basics BB, PT
HackerOne US FedRAMP Basics BB, PT, VD
Hackrate Hungary GDPR Basics BB, PT, VD
HACKTIFY Hungary GDPR Basics BB, PT, VD
Hackrfi Finland GDPR Basics BB
Immunefi N/A None Basics BB
Inspectiv US FedRAMP Basics VD
Intigriti Belgium GDPR Basics BB
Open BB Bangladesh ISO-29147 Twitter Account BB
Ravro Iran ISO-29147 Basics BB
RedStorm Singapore None Basics BB, VD
SafeHats India ISO-27001 Basics BB, VD
Safevuln Vietnam None Basics BB
Secuna Phillipines ISO-29147 DoB, Addr, PoI BB, PT,
Nationality Audit
SecureBug Sweden GDPR Basics BB, PT, RT
SlowMist China N/A Application BB, BC, RT
Swarmnetics Singapore N/A Application BB, PT, VD
Synack USA ISO-27001 Application BB, PT, VD
TestBirds Netherlands GDPR Loc, DoB BB, PT
TheBugBounty Malaysia N/A N/A BB, PT
Continues on next page
31
Platforms Location Stnds/Regs Personal Info Services
v1bounty Germany GDPR Basics BB, VD
Vulbox China None Tele#(+86) BB, VD
Vulnerability Lab Germany GDPR Basics BB
Vulnscope Chile N/A Country, DoB BB, PT
WhiteHub Vietnam None Basics BB, PT
YesWeHack France GDPR N/A BB, VD
Yogosha France GDPR Community BB
Zerocopter Netherlands GDPR N/A BB, VD
Registering for Different Platforms
Using the data collected from the different platforms, the list was reduced to platforms
with a minimum requirement for registration information (first and last name, an email
address, and a username). This reduction was done due to the time and effort it would take
to create an account and submit a bug report in a malicious scenario.
Once registered on the platform, the programs hosted on each platform were in-
vestigated. Some of the surprising findings were the same vendors being hosted on
different platforms
3
and American companies were hosting programs on platforms from other
countries. For example, Sony is hosting a public program on an Asian platform.
This is the final list of platforms used in this study:
3
Medtronic was one of these companies that had programs on HackerOne and BugCrowd. This was
discovered in looking at Medtronic’s vulnerability disclosure website and communicating with Medtronic’s
security team about their bug-bounty program
32
Table 5.2: Selected Third-Party Platforms with Geographical, Standard Compliance, and
Year Established
Company Location Year Est. Compliance
BugHunt Brazil 2020 None
BugBase India 2021 29147
BugBounter Turkey 2020 GDPR
BugBounty.jp Japan 2015 ISO-29147
BugBounty.ru Russia 2021 ISO-27001
BugCrowd US 2012 FedRAMP
bugv Nepal 2020 None
Federacy USA 2018 SOC2
HackenProof Estonia 2017 GDPR
HackerOne US 2012 FedRAMP
HackRate Hungary 2020 GDPR
Hackerfi Finland 2016 GDPR
HACKTIFY Hungary 2020 GDPR
Immunefi Virtual 2020 GDPR
Inspectiv US 2018 FedRAMP
Intigriti Belgium 2016 GDPR
Ravro Iran 2019 N/A
RedStorm Singapore 2018 None
SafeHats India 2012 ISO-27001
SafeVuln Vietnam 2014 None
SecureBug Sweden 2019 GDPR
WhiteHub Vietnam 2019 None
33
File Attachments with Vulnerability Reports
I registered for 22 platforms to identify the restrictions and file types for report
attachments. By clicking a link or button that says ‘submit report’ or ‘create a report,’ every
one of the platforms has a similar reporting format in how the researcher is to complete a
valid bug report.
Each platform requested the same elements within the report [16]:
A description of what service or product is affected by the vulnerability.
How the vulnerability can be identified, demonstrated, or reproduced.
The impact the vulnerability has on a service or product.
The difference between the platforms lies in the size, count, and type of file attachments.
When a file type is not allowed, a researcher can not upload that file to the report. When
the size of a file is too big, or the combination of files size is over the limit, a notice appears
above the report with a message such as ‘file size over limit.’
The following is a collection of the file size and count restrictions in each platform’s
report:
34
Table 5.3: Third-Party Platforms Report Attachment Restrictions on Size and Count
Company Location Max Size Max Count
Bug Hunt Brazil No Limit 10
Bug Base India 25 No Limit
BugBounter Turkey 50 1
bugbounty.jp Japan 5 5
BugBounty.ru Russia 30 No Limit
BugCrowd US 50 20
Bugv Nepal 5 5
Federacy USA N/A N/A
HackenProof Estonia 50 5
HackerOne US 250 No Limit
HackRate Hungary 150 No Limit
HACKTIFY Hungary 250 No Limit
Hackerfi Finland No Limit 1
Immunefi Virtual 8 20
Inspectiv US 10 20
Intigriti Belgium 5 30
Ravro Iran 100 No Limit
RedStorm Singapore No Limit No Limit
SafeHats India No Limit No Limit
Safevuln Vietnam 50 3
SecureBug Sweden 50 10
WhiteHub Vietnam 50 10
35
Next, I implemented tests to identify the types of files that are allowed as report
attachments. File extensions were chosen based on the findings from the set of metadata
of malware samples (i.e. over 35 million). All the file extensions were categorized into a
general set of file types. The file types were split into these categories: images, videos, links,
executable, compressed, documents, and PDF.
By examining the metadata of the malware machine, 95 unique file extensions were
identified, and of those, 40 contributed to at least 1000 samples of the same file extension.
After gathering data on each of the file extensions that were considered ‘significant’, the file
extensions were organized into categories based on similarity. For example, since jpg and
png are file extensions that use an image format, they are grouped together in an ‘image’
category. These extensions are tested on the selected platforms. Any category that contains
at least one type of file extension is classified as an attachment for each platform.
These extensions were categorized and tested:
Image: bmp, dex, fpx, gif, jpg, png, riff, swf
Videos: m2t, mp4, mts
PDF: pdf
Document: doc, docx, ppt, xls, xml, rtf
Executable: (no extension), dll, exe, php, pl, py, sh, rb
Compressed: gz, rar, tar, zip
Links: chm, html, lnk
Of all the platforms examined, only one did not have any options for file attachments:
Federacy, as depicted in Table 5.4. This means a hacker is not able to attach malware to a
vulnerability report. Thus, showing that every platform is susceptible to malware infection
when security precautions are not in place.
After testing, this was the results on each platforms accepted file types:
36
Table 5.4: Accepted File Types on Bug-Bounty Platforms
Company Img Vid PDF Doc Exe Zip Link
Bug Hunt
Bug Base
BugBounter
bugbounty.jp
BugBounty.ru
BugCrowd
Bugv
Federacy
HackenProof
HackerOne
HackRate
HACKTIFY
Hackerfi
Immunefi
Inspectiv
Intigriti
Ravro
RedStorm
SafeHats
Safevuln
SecureBug
WhiteHub
37
Current Malware Detection Plans
Based on PQ1 (preliminary-guiding question), the overall answer is that there are no
scans or detections performed on to a bug report before opening and validating the report.
This is because bug-bounty platforms use a web-based report-tracking system to organize all
submissions in a bug-bounty program. Other than using a basic virus scanning tool, there
is no plan in place for scanning each report for malicious scripts or malware.
Differences in Platforms
In PQ2, there are several differences between platforms from the U.S. and other
countries. For example, any platforms originating from the Americas or Asia do not use
GDPR
4
, because this is a regulation of the European Union. Each platform also offers
a different set of services to vendors, not just bug-bounty programs. In addition, each
platform collects a different set of information about the researcher. Some need a username,
full name, and email (which could be easily falsified). Other programs require additional,
personal information such as country of origin, bank account information, passport number,
address, and phone number. Some programs even restrict who is allowed to join a platform,
meaning they only allow people within the country of origin to join their platform. Appendix
A contains tables with the results from this data collection.
These results show that most platforms follow some sort of standard or regulation. The
main ISO standards are ISO-27001 and ISO-29147, and the main regulations are GDPR and
FedRAMP. If a platform does not comply with a standard or regulation, there is usually more
identification required to join the platform. However, there are still a handful of platforms
that do not comply to any standards or regulations, and only require the basics to sign up as
4
General Data Protection Regulations
38
a researcher. This makes these platforms a prime target for hackers to exploit the platform.
Relation of Malware and File Types
I wanted to analyze each platform and figure out the types of malware to which the
vendor may be exposed by the report attachments. It is crucial to know what types of
files can have malware attachments in order to assess the potential attack vectors. A more
in-depth analysis of this is done in a case study in the next chapter.
Of all the platforms in this study, all but one allows for images. Images consist of file
extensions such as gif, jpg, png to name a few. The next most commonly accepted file type
is PDF; 17 platforms accepted pdf as file attachments. Videos are accepted as a report
attachment in fifteen platforms. Video files include m2t, mts, mp4 file extensions. Only
fourteen of the platforms allow for text-based documents. Text files include ppt, doc, xml,
rtf file extensions.
Only nine of the platforms allow compressed files in a bug report. A compressed file
has several different extensions, but was tested with a zip, rar, and gz. A compressed file
is the second most common way to embed malware
5
; this is due to the lack of visibility of
the contents of a zipped file prior to being downloaded. A zipped file does not need to be
extracted before malware can infect a computer, the file can spread malware in its zipped
form.
Links are allowed as attachments in eight platforms. The links were tested using html,
lnk and chm file extensions. Only seven platforms allow for scripts, which is the most
common way to spread any type of malware. The script extensions that were tested include
dll, exe, and scripts from programming languages like Python, Java, Perl, and Ruby. If a
platform allows for scripts, the reports would have to be scanned for malicious scripts before
5
evidence from VirusTotal
39
downloading the report. If not, for these seven companies, this is a major risk for potential
exploitation.
40
ANALYSIS
This chapter provides an analysis of the data, answers to the GQM questions, and
illustrates the findings from the observational case study. The analysis of the data provides
the answers to the GQM questions. Then a study of malicious files embedded into bug
reports is applied to create a conceptual framework for characterizing attack vectors. The
case study validates the decisions for file extensions and types of malware used in the study.
Observational Case Study
According to Yin’s Case Study Research, a case study is used with the goal of testing
the different ideas that would contribute to the final solution [36]. This case study is used
to formulate the framework and answer the questions from the GQM. This study answers
the ‘what’, ‘why’, and ‘how’ a conceptual framework is a solid solution for characterizing
potential attack vector in bug reports.
So far, the study has provided information about the chosen bug-bounty platforms,
divided the file extensions into seven categories, identified the three cybersecurity frameworks
that could be used to improve the security for bug-bounty programs, identified the types of
malware as potential report attachments, and identified the file extensions that are allowed in
reports. Following is an illustration of the relationship between file extensions and malware
using a large sample size of malware.
The malware samples were provided by Hoplite Industries. Using the malware sample
metadata, I was able to calculate the relationship between file extensions and malware.
All the metadata was sourced from a large database and information was retrieved by
using SQL
1
queries. These queries produced a list of all the file extensions used in over 35
million malware samples. For this case study, the list was reduced to file extensions that
1
Sequence Query Language
41
had more than ten samples in a file extension.
Table 6.1: Data Collection of File Extension and Count on Malware Samples with More
than 20 Samples per Extension
Extension Count Extension Count Extension Count
exe 18318271 html 10175562 (no ext) 2813930
dll 2180563 zip 690314 pdf 291078
rar 246302 m2t 183796 gz 82844
jpg 77256 doc 71797 dex 54009
lnk 29421 png 28290 xml 20309
gif 18915 php 18192 xls 17697
fpx 16102 xlsb 12898 swf 11072
sh 4972 pl 4797 rtf 4311
mp3 3619 bmp 3407 chm 2366
docm 2354 xlsm 1827 mp4 1691
riff 1310 mts 1072 asf 836
bz2 762 plist 662 py 645
wmf 608 docx 595 tar 582
ttf 512 ogg 462 xlsx 417
ppt 415 wav 356 tif 339
svg 229 (386) 207 a 207
torrent 145 mov 110 rsrc 101
eps 92 dotm 76 m4a 59
rb 55 xlam 53 webp 49
otf 43 mpg 31 pptx 26
webm 23 acr 21
42
With the file extension collection, the list was categorized and reduced to file extensions
with no less than 1000 samples or commonly used file extensions:
Table 6.2: Selected File Extensions with File Count and Category(Type)
Extension Count Category Extension Count Category
exe 18318271 executable html 10175562 link
(no extension) 2813930 executable dll 2180563 executable
zip 690314 compressed pdf 291078 Adobe
rar 246302 compressed m2t 183796 video
gz 82844 compressed jpg 77256 image
doc 71797 document dex 54009 image
lnk 29421 link png 28290 image
xml 20309 document gif 18915 image
php 18192 script xls 17697 document
fpx 16102 image xlsb 12898 document
swf 11072 image sh 4972 script
pl 4797 script rtf 4311 document
mp3 3619 audio bmp 3407 image
chm 2366 link docm 2354 document
xlsm 1827 document mp4 1691 video
riff 1310 image mts 1072 video
py 645 script docx 595 document
tar 582 compressed ppt 415 document
mov 110 video rb 55 script
Once there was an adequate sample size of each file extension, the type of malware
43
was identified for that file extension. This data is used to create a diagram that shows the
relationships between file types and malware types.
Table 6.3: Relationship between Types of Malware and File Extensions
File Ext Ad PUA/P Spy Script Trojan Ransom Virus Worm
no ext
bmp
chm
dex
dll
doc
docx
exe
fpx
gif
gz
html
jpg
lnk
m2t
mp3
pdf
php
pl
png
Continues on next page
44
File Ext Ad PUA/P Spy Script Trojan Ransom Virus Worm
ppt
py
rar
rb
riff
rtf
sh
swf
tar
xls
xml
zip
The goal of this observational case study was to create a visual of the relationship
between types of malware and file extensions. This was done by using malware samples
as evidence to back up how this conceptual framework characterizes the attack vectors for
each platform. This case study validates the legitimacy of the behavioral diagram in this
conceptual framework and provides proof to answer questions from the GQM.
Q1: Are there any standards and regulations implemented in the platforms that prevent
malware infection through a vulnerability report?
There are no standards and regulations in place on the platforms that contain a clause
or requirement for malware detection. This oversight opens up the potential for non-public
bug reports to be exposed to the public, sold on the black market, and used to exploit a
45
company. This answer is supported by reviewing every standard and regulation used by the
platform to ensure the phrase ‘trust a third party services’ or ‘malware detection’ does not
exist in the current regulations.
Q2: Using the data collected, what file types are most commonly used and what is the type
of malware that corresponds with that type?
By analyzing the collection of data, the connection between malware and file types is
illustrated in the next section. However, one important detail to note is that use of executable
and script files makes a company susceptible to every type of malware in our case study (i.e.,
Adware, Spyware, Ransomware, Virus, Worm, Trojan, PUA/PUP, and Stego malware). The
answer to the second question in the GQM is that images are the most commonly allowed
file type between the platforms. This leaves Trojans and Stego malware as the only potential
types of malware used in reports based on our study. This answer is supported from the
findings in table 5.4,
2
6.2,
3
and 6.3.
4
Q3: By illustrating the relationship between file extensions and malware types, can this
conceptual framework improve the ability for vendors to assess the safety of bug reports?
The framework is used to improve the ability for vendors to choose the best platform
that balances report attachment options with security by characterizing the potential attack
vectors. This is done by providing the ability to characterize the potential attack vectors
for each platform. The framework provides an illustration of the structural and behavioral
guide of the bug-bounty report verification process. The structural diagrams illustrate the
connections between the components and the behavioral diagram guides the vendor with a
2
Accepted File Types for Bug-Bounty Platforms
3
Malware Sample File Extensions, Count, and Category
4
Relationship between Malware Types and File Extensions
46
step-by-step guide on how to use the framework, and how each component interacts.
47
CONCEPTUAL FRAMEWORK
The objective for this conceptual framework is to help vendors choose a platform by
assessing the potential attack vectors based on the bug-bounty platform. This is to be used
as a tool to assist vendors. This is not to be used to detect malware, but to understand the
potential attack vectors that are introduced by different types of malware.
A conceptual framework is an overarching argument about the importance of the
research and how different concepts or theories are connected. It defines not only why an
investigation is important but also how it should be done [23]. The framework is portrayed
as figures and diagrams, illustrating the connection between concepts and the importance
of the study. There is no standard format for the design of a framework, only the overall
purpose of the framework.
The purpose of a conceptual framework is to articulate the logical connection between
the problem identified and the methodological innovations, all of which can evolve over time
as the understanding of the material increases [23]. This framework is used to show the
connections between concepts and create thoughtful questions that help reach an answer to
the overall problem that exists in a study. Since this study relates to malware detection,
the purpose of this framework is to create a procedure for safely handling bug reports by
assessing potential attack vectors from malicious report attachments.
A conceptual framework was chosen because of its use in research to combine well-
studied components to create a new theory: to show that there has been plenty of research
done for each of the necessary components, but these components have not been connected
before. In this framework, file attachments, malware, and bug-bounty platforms are joined
together.
There is a plethora of studies on malware available through academic articles and
security companies. VirusTotal is used to gather data about the file extensions that have
48
been used for malware, which is the source of the list of malicious file identities. The use
of existing malware articles and websites that have trustworthy malware detection software
provides validity to the decision to use the information found in these resources.
Investigating the cybersecurity frameworks from Chapter Three and the standards and
regulations used by the platforms is evidence that malware detection is not a concept that
has been considered in this context. Instead, the standards recommend the platforms have
a plan of action in place in the event of a data leak. This investigation into the procedures
and activities of the platforms shows that malware detection or scanning file attachments is
not specified in any platform.
Therefore, this conceptual framework provides an illustration of the relationship
between malware, file attachments, and the potential attack vector used to exploit bug-
bounty platforms.
Components of the Conceptual Framework
In a conceptual framework the components are used to make up a theory or phenomenon
that creates the final product (results of the study). The components in the conceptual
framework are restated after the exploration and analysis of the data: file attachments,
malware types, and bug-bounty platform. The following explains the importance and role
of these items:
File Attachments
During the research process, files were sorted into seven categories: Documents, Images,
Videos, Compressed, Executable, Links, and PDF. This was done to create a clean visual
that can be easily explained. During the case study, the relationship between file types and
malware types was analyzed.
49
Image: bmp, dex, fpx, gif, jpg, png, riff, swf
Videos: m2t, mp4, mts
PDF: pdf
Document: doc, docx, ppt, xls, xml, rtf
Executable: (no extension), dll, exe, php, pl, py, sh, rb
Compressed: gz, rar, tar, zip
Links: chm, html, lnk
Malware Types
The purpose and results of the case study validate the decision to include malware
types as a component of this framework. There are many different types of malware, but
for illustration purposes, it is narrowed to the common types of malware that were found
in over 35 million samples. These nine types of malware cover all types of files that can be
attached to a report and have a different attack vector. The different types of malware that
are used in this case study are Adware, PUA/PUP, Ransomware, Spyware, Trojan, Virus,
Worm, Stego and Script-Based malware.
Bug-Bounty Platforms
The platform is included as a component of the framework because there is no
correlation between the standards followed and the types of files accepted by the platform.
This correlation analysis is done by comparing tables 5.2 and 5.4, and combining the data to
illustrate how each standard relates to the file types. It’s important to note that not every
platform that complies to FedRAMP or GDPR allows for every file type, and that there is
an overlap. For the platforms that follow each compliance, the following table indicates the
potential file type allowed.
50
Table 7.1: The Correlation Between File Types and Compliance
File Type ISO-29147 ISO-27001 FedRAMP GDPR
Images
Videos
Documents
PDF
Compressed
Executable
Links
Discussion
The takeaways from the case study is an understanding of the files types used by
different types of malware. In addition, there is a suggestion on the location to modify the
current ISO-29147 standards and hypothesize on how the framework works when presented
to a vendor.
ISO Modification Recommendation
If there is a place in the current report handling process that could improve the security
for vendors when handling reports, it is in the verification step. By assuring the report is
legitimate (not only in the content of the report, but also in the attachments) the report
soundness is ensured.
51
Figure 7.1: Summary of Vulnerability Handling Process from ISO-29147[16]
Hypothesis of Conceptual Framework
Trying to cover the entire attack surface for all malware is impractical, so the goal is to
make the attack surface manageable. However, by knowing what files extensions are used,
the attack surface is reduced to a manageable size. The goal for this conceptual framework
is to lead a vendor through the process of understanding the types of malware used in
their platform’s bug reports to assess the potential attack vectors (based on the current
knowledge obtained from researching these bug-bounty platforms). By understanding the
potential attack vectors, the vendor can monitor computer functionality and monitor for the
modification of files or other data.
From the GQM, the goal is to add the procedure of malware detection specifically in
vulnerability reports and characterize potential attack vectors. Therefore, the contribution
from this research is understanding that there are trade-offs to having restrictions on the
report’s file attachments - convenience or security. This conceptual framework is meant to
be used by a vendor whose goals is to improve the security of bug reports. The conceptual
framework is compiled to link all the different components necessary to reach this goal.
52
Justifying The Theory
The theory of this conceptual framework is the following: an understanding of file types
can help identify types of malware and thereby characterize the potential attack vectors
introduced by a vulnerability report.
In order to assemble a conceptual framework, it is necessary that the evidence is
organized and structured into a concise and precise manner [29]. This is done by performing
studies to validate the theory(s).
According to Shull and Sjoberg [27, 29], the process to building a theory involves
constructs, propositions, explanations, and scopes. The theory is built using the following
steps:
1. Defining the Constructs of the Theory
2. Defining the Propositions of the Theory
3. Providing Explanations to Justify the Theory
4. Determining the Scope of the Theory
5. Testing the Theory Through Empirical Research
Building the Theory
In the context of this idea, these are the core assumptions followed:
The vendor does not use a virtual environment to open reports.
The vendor believes the researcher has no malicious intent when sending a report.
The platform does not scan any reports for malicious files.
The vendor does not use a specialized malware detection software.
All reports have been validated and triaged by the platform.
Using these assumptions, the framework will be composed of three structural diagrams
and one behavioral diagram.
53
Following the five steps to build a theory in software engineering, these are the defined
constructs:
C1: Prevention (system monitoring)
C2: Communication (report opening and downloading procedures)
C3: Coordination (platforms and vendors)
C4: Documentation (allowed file attachments)
C5: Validation (in scope and valid)
C6: Security (malware)
C7: Detectability (malware detection)
C8: Knowledge (file extension and malware relationship familiarity)
Next, are the defined propositions:
P1: The use of report analysis on the report contents improves malware prevention.
P2: The use of report analysis increases security for the vendor.
P3: Report analysis positively affects the validation of reports.
P4: The use of report analysis reduces the potential for vulnerabilities to be exploited from
the report content.
P5: The knowledge of malware is reduced without using the report analysis for malware.
P6: The positive effects of report analysis are reduced if there is not enough communication.
P7: Report analysis positively affects coordination between vendor and platform.
P8: Poor report analysis affects documentation for vendor.
The explanations are used to understand why the theory is necessary and important:
E1: By understanding the relationships between file extensions and malware, the safety of
viewing reports after malware detection is improved, and the company is protected from
malware exposure.
E2: By understanding which attachments each platform allows, a company can choose a
platform that has a restricted set of file attachments.
54
E3: By illustrating the connections between the scopes and constructs, there is an
understanding of the reason report analysis for malware is important and what aspects
of the bug-bounty life cycle is affected.
Defining the scope has been part of the observational study, but this provides a concise
list of the scopes of the theory in terms of validity and interest of each scope.
S1: Technology
Validity of Scope: The extension and type of malware that are most common and
most likely to be allowed as file attachments in reports using over 35 million malware
samples.
Interest of Scope: Of the 95 different extensions used in over 35 million malware
samples, the focus is on only the most commonly used file extensions, omitting any
extensions that have less than 1000 samples.
S2: Actor
Validity of Scope: Data is validated by joining and exploring 22 different bug-bounty
platforms from an original total of 49 investigated.
Interest of Scope: Platforms of interest required minimal information needed to
register. This information is falsified with minimal effort (i.e. username, email, and
name are required).
S3: Activity
Validity of Scope: Data is validated by a list of allowed attachments for each platform.
Within a platform, only accepted file attachments are allowed.
Interest of Scope: Data on file restrictions. Categorizing file extensions into groups.
S4: Malware Detection
55
Validity of Scope: Every malware sample has a reference to the metadata of the sample
from VirusTotal. Using VirusTotal helped to classify the type of malware identified in
the sample along with the metadata of the malware file.
Interest of Scope: The relationship between types of malware and file extensions.
Figure 7.2: Structural: A UML Theory Diagram for the Effects of Malware Analysis in
Reports
The final step to building a theory has already been done and will continue to be tested
and updated when necessary.
The Relationship Between Bug Report Attachments and Malware
Visuals were created based on the research findings on the relationship between file
types and malware types. Figure 7.3 provides the types of malware used by types of files.
A complete list of each file extension can be found in Table 6.2. Each type of malware has
a different set of files used to attack (different types of malware that have different names
56
but are still classified under a particular type of malware). In the picture these are called
‘subset malware.’ Each bug includes a symbol of the malware’s actions.
Figure 7.3: Structural: Map of Malware Types with Identified File Types
57
To understand the importance of this research, a UML class diagram was created to
explain the interactions between the components of the framework.
Figure 7.4: Structural: A UML Class Diagram Illustrating the Structure of the Framework
Figure 7.4 shows four components in green. Two of those components have been
separated into more detailed objects because a report can contain different types of files
and different types of malware. A company has to use a platform(except for the in-house
58
platforms specified in the background section), so the platform has an input set to 1.
Using the platforms from the study, a report can contain zero attachments up to several
attachments (some are unlimited). For each report submission, there is only one report
submitted, so that connection is set as 1 to 1. Finally, there is a red line that connects the
classes Attachments and Malware. This connection used to be 0 to 0, this research changes
that ‘0..0’ to ‘0..*’. Prior to this research, there was never a consideration or procedure in
place for detecting malware in bug-bounty reports.
In Figure 7.5, the steps of using the framework are illustrated. It also illustrates how
each variable impacts the other variables. The flowchart explains which diagrams are used
to lead to the next step.
The vendor is set as the control variable because the vendor (company) does not change.
The independent variables are the bug-bounty platforms and the potential malware presented
in these findings. They are independent because the platform chooses the file restrictions
and the potential malware is based on actual malware samples.
The dependent variables depend on the independent or mediator variables. The report
attachment differs based on the prospective bug-bounty platform. The report soundness
(legitimacy of the report) depends on whether there was use of malware detection in the
report, affecting the potential attack vector on the vendor.
The moderator variable is how the case study affects the knowledge of the vendor;
more specifically, this gives the vendor an idea of the types of malware used. This moderator
variable can improve malware detection by reducing the types of malware to detect. The
mediator variable doesn’t affect the report soundness but it enables the understanding of
how knowledge of the malware attack vector improves malware detection.
59
Figure 7.5: Behavioral: Flowchart for Companies Using a Bug-Bounty Platform to Assess
Potential Attack Vectors
60
How to use the Conceptual Framework
The vendor uses the UML class and theory diagrams and a malware diagram to illustrate
the structure of this framework. The behavioral diagram is illustrated using the flowchart.
The flowchart is used to guide the vendor through the framework.
Conceptual Framework Use Cases
The actor most likely to use this conceptual framework is a company that is looking for
a bug-bounty platform to host their program or a company that has a bug-bounty program
with a platform and wants to determine the security risks for reports.
First, the vendor finds a potential/current platform. This is done by using Table 5.2 and
5.3 to identify file types and file restrictions. Once the vendor has identified the platform that
best fits their needs and has identified the file types, they use the malware diagram (Figure
7.3) to identify their potential malware attacks. The vendor can then choose a malware
detection that best fits their potential malware attack. By following these steps, the vendor
can increase the report soundness and reduce the malware attack vector.
The framework could also be used to compare platforms to determine which platform
in better suited, by iterating through the flowchart for each platform of interest. The reason
this is a use case is because not every vendor wants the most secure platform (convenience
over security). There is a need for a balance between what file attachments are desired by
the vendor and the size of the attack surface the vendor is willing to expose. For example, if
the vendor decides that images and compressed files are beneficial report attachments, that
means that the vendor could expose themselves to Trojan, Adware, Stego malware, Virus,
and PUA/PUP.
61
CONCLUSION
The results from this research show that if a vendor does not scan reports for malware,
there is disastrous potential for malware attacks. For the vendors that don’t used malware
detection or a virtual environment to view reports, I have compiled a resource connecting
malware types to file extensions to help characterize potential attack vectors introduced to
the vendor using the report attachments. There are some file types that allow more types
of malware than others, but there is a trade-off to consider: malicious attack vectors versus
the restrictions on file attachments.
The study also concludes that the standards used by the platform can benefit from
adding some type of malware detection clause or advising the use of a detonation chamber
1
for the platform to uphold. However, it is still the responsibility of the vendor to maintain
proper security measures that include malware detection for reports.
This research provides a new perspective of where to detect malware and that even
when a company opens themselves up to a program to improve their security, there is a need
for caution in balancing security with convenience. It can be beneficial to host a program
on a platform with no file restrictions, but that decision all depends on the size of the attack
surface a vendor is willing to expose.
Future Work
For future work, a thorough study into each type of malware can be done, along with
increasing the sample size of the relationship between malware types and file extensions.
The list of file types can be expanded into a study of each file extension and its relationship
with malware types.
1
Virtual environment to test for malicious files
62
In addition, on the researcher’s side of the platform’s web interface, every vulnerability
submission page has a text box that can be used to add a malware script in the report,
meaning the malware can embed itself into the report instead of attaching to it. It is worth
looking into the impact this has on malware detection.
Also, not all malware is a pure type of malware. Many samples of malware are classified
as ‘hybrid’ malware
2
(i.e. Trojan Virus or Ransom Ad). The interest is in the impact the
complex attacks has on the framework.
In addition to hybrid malware, an investigation into Stego malware and its impact on
file attachments is warranted since Stego malware is only briefly mentioned in this research.
Stego malware is of interest because of its ability to obscure the contents in its file, turning
any attack into the accepted file extension used as a report attachment.
Motivation and Contribution
The motivation for this research comes from curiosity, and more specifically, a desire to
determine the security of bug-bounty programs for vendors. There was no confirmation on
whether vendors could trust that their bug reports do not contain anything malicious, and,
therefore, the goal was to see if this confirmation was possible.
Using the framework provides a way for vendors to assess the potential attack vectors,
and to understand that there are trade-offs in having restrictions on file attachments for a
bug-bounty platform. Using the tables and diagrams to gain knowledge of the relationship
between malware and file types, a list of the file types allowed by each selected platform, and
a summary of each standards used by the platform, the vendor can proceed with caution to
hosting a bug-bounty program and viewing the reported vulnerabilities. My contribution is
in providing this framework to help vendors choose a platform that balances the trade-offs
2
Malware that uses different types of malware to perform a complex attack, an attack that uses multiple
attack vectors.
63
between safety and convenience of report attachments.
This conceptual framework is used to illustrate the importance of understanding the
relationship between malware types and file attachments, and understanding the potential
attack vectors that accompany a bug-bounty report. Until standards are updated to include
a scanning requirement performed by the platform, or the platform advising vendors to use
a detonation chamber, vendors must do their part to maintain information security for their
customers and services. As long as bug-bounty programs exist, and as long as the platforms
are not scanning for malware, the reports are a company’s greatest vulnerability.
64
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68
APPENDICES
69
APPENDIX A
BUG BOUNTY PLATFORM TABLES
70
Table 5.3: Third-Party Platforms Report Attachment Restrictions on Size and Count
Company Location Max Size Max Count
Bug Hunt Brazil No Limit 10
Bug Base India 25 No Limit
BugBounter Turkey 50 1
bugbounty.jp Japan 5 5
BugBounty.ru Russia 30 No Limit
BugCrowd US 50 20
Bugv Nepal 5 5
Federacy USA N/A N/A
HackenProof Estonia 50 5
HackerOne US 250 No Limit
HackRate Hungary 150 No Limit
HACKTIFY Hungary 250 No Limit
Hackerfi Finland No Limit 1
Immunefi Virtual 8 20
Inspectiv US 10 20
Intigriti Belgium 5 30
Ravro Iran 100 No Limit
RedStorm Indonesia No Limit No Limit
SafeHats India No Limit No Limit
Safevuln Vietnam 50 3
SecureBug Sweden 50 10
WhiteHub Vietnam 50 10
71
Table 5.4: Accepted File Types on Bug-Bounty Platforms
Company Pic Vid PDF Doc Executable Compressed Link
Bug Hunt
Bug Base
BugBounter
bugbounty.jp
BugBounty.ru
BugCrowd
Bugv
Federacy
HackenProof
HackerOne
HackRate
HACKTIFY
Hackerfi
Immunefi
Inspectiv
Intigriti
Ravro
RedStorm
SafeHats
Safevuln
SecureBug
WhiteHub
The file attachments have specific file types that belong to each category:
Pictures: jpg, fpx, swf, riff, dex, png, gif, bmp
Videos: mp4, mts, m2t
Adobe: pdf
Document: doc, xls, xml, rtf, docx, ppt
Executable: dll, exe, (no extension), pl, py, sh, rb, php Compressed: zip, rar, gz, tar
Links: html, lnk, chm
72
Table 5.1: Third-Party Platform Data Collection on Registration Information,
Geographical Location, Standard Compliance, and Service Options for all Identified
Platforms
Platforms Location Stnds/Regs Personal Info Services
Antihack.me Singapore N/A N/A BB, PT, RT
BB Carribean Carribean ISO-27001 Application BB
BB Switzerland Switzerland GDPR Application BB
BugHunt Brazil None Basics BB, VD
BugBase India ISO-27001 Country of BB, PT, VD
Origin
BugBounter Turkey GDPR Basics BB
bugbounty.jp Japan ISO-29147 Basics BB
bugbounty.sa Saudi Arabia N/A Bank Account, BB
Tele #
bugbounty.ru Russia ISO-27001 Basics BB
BugCrowd US FedRAMP Basics BB, VD
Bugv Nepal None Basics BB, PT, VD
CrowdSwarm UAE N/A DoB, Tele #, BB, PT
Addr, Passport
Cyber Army Indonesia N/A Indonesia BB, VD
Indonesia Citizenship
Cyscope Chile None Country BB
Detectify Sweden GDPR TBD VD
EpicBounties Spain GDPR DoB, Addr BB
LATAM Passport
Federacy US SOC2 Basics BB, PT, VD
FindBug Kosovo GDPR Complete CTF BB, VD
Frontal UAE N/A Application BB, RT, VD
GObugfree Switzerland GDPR Basics BB, PT
HackenProof Estonia GDPR Basics BB, PT
HackerOne US FedRAMP Basics BB, PT, VD
Hackrate Hungary GDPR Basics BB, PT, VD
HACKTIFY Hungary GDPR Basics BB, PT, VD
Hackrfi Finland GDPR Basic BB
Immunefi N/A None Basics BB
Inspectiv US FedRAMP Basics VD
Intigriti Belgium GDPR Basics BB
Open BB Bangladesh ISO-29147 Twitter Account BB
Ravro Iran ISO-29147? Basics BB
RedStorm Indonesia None Basics BB, VD
SafeHats India ISO-27001 Basics BB, VD
Continues on next page
73
Platforms Location Stnds/Regs Personal Info Services
Safevuln Vietnam None Basics BB
Secuna Phillipines ISO-29147 DoB, Addr, PoI BB, PT
Nationality Audit
SecureBug Sweden GDPR Basics BB, PT, RT
SlowMist China Application BB, BC, RT
Swarmnetics Singapore N/A Application BB, PT, VD
Synack USA ISO-27001 Application BB, PT, VD
TestBirds Netherlands GDPR Loc, DoB BB, PT
TheBugBounty Malaysia BB, PT
v1bounty Germany GDPR Basics BB, VD
Vulbox China None Tele#(+86) BB, VD
Vulnerability Lab Germany GDPR Basics BB
Vulnscope Chile Country, DoB BB, PT
WhiteHub Vietnam None Basics BB, PT
YesWeHack France GDPR BB, VD
Yogosha France GDPR Community BB
Zerocopter Netherlands GDPR BB, VD
74
Table 5.2: Selected Third-Party Platforms with Geographical Location, Standards
Compliance, and Year Established
Company Location Year Est. Compliance
BugHunt Brazil 2020 None
BugBase India 2021 29147
BugBounter Turkey 2020 GDPR
BugBounty.jp Japan 2015 ISO-29147
BugBounty.ru Russia 2021 ISO-27001
BugCrowd US 2012 FedRAMP
bugv Nepal 2020 None
Federacy USA 2018 SOC2
HackenProof Estonia 2017 GDPR
HackerOne US 2012 FedRAMP
HackRate Hungary 2020 GDPR
Hackerfi Finland 2016 GDPR
HACKTIFY Hungary 2020 GDPR
Immunefi Virtual 2020 GDPR
Inspectiv US 2018 FedRAMP
Intigriti Belgium 2016 GDPR
Ravro Iran 2019 N/A
RedStorm Singapore 2018 None
SafeHats India 2012 ISO-27001
SafeVuln Vietnam 2014 None
SecureBug Sweden 2019 GDPR
WhiteHub Vietnam 2019 None
75
Table A.1: Bug-Bounty Platform Resources
Company Weblink
BountySource https://bountysource.com
BugHunt https://www.bughunt.com.br/index.html
BugBase https://bugbase.in/
BugBounter https://bugbounter.com/
Bug Bounty Caribbean https://bugbountycaribbean.com/
BugBounty.jp https://bugbounty.jp/
BugBounty.ru https://bugbounty.ru
BugBounty.sa https://bugbounty.sa/
Bug Bounty Switzerland https://bugbounty.ch/
BugCrowd https://www.bugcrowd.com/
bugv https://bugv.io/
Cobalt https://www.cobalt.io/
CrowdSwarm https://www.crowdswarm.io/
Cyber Army Indonesia https://www.cyberarmy.id/en
Cyscope https://cyscope.ch
Detectify https://detectify.com/
Epic Bounties https://www.epicbounties.com/
Federacy https://federacy.com
FindBug https://findbug.io/
Frontal https:frontal.io
GOBugFree https://gobugfree.com/
HackenProof https://hackenproof.com/
HackerOne https://www.hackerone.com/
HackRate https://hckrt.com/
Hackrfi https://hackr.fi/
HACKTIFY https://www.hacktify.eu/en/home/
Immunefi https://immunefi.com/
Inspectiv https://www.inspectiv.com/
Intigriti https://www.intigriti.com/
Open Bug Bounty https://www.openbugbounty.org//
Ravro https://www.ravro.ir/
RedStorm https://www.redstorm.io/
SafeHats https://safehats.com/
SecureBug https://securebug.se/
SlowMist https://www.slowmist.com/
Swarmnetics https://www.swarmnetics.com/
Continues on next page
76
Company Weblink
Synack http://synack.com/
TestBirds https://testbirds.com/en/
The Bug Bounty https://thebugbounty.com/
V1 Bug Bounty https://v1bounty.com/
VulBox https://vulbox.com/
Vulnerability Lab https://vulnerability-lab.com/
Vulnscope https://vulnscope.com/
SafeVuln Viettel https://safevuln.com/
WhiteHub https://whitehub.net/
YesWeHack https://yeswehack.com/
Yogosha https://yogosha.com/
Zero Day Initiative https://zerodayinitiative.com/
Zerocopter https://zerocopter.com/
77
APPENDIX B
MALWARE METADATA
78
Table 6.1: Data Collection of File Extension and Count on Malware Samples with More
than 20 Samples per Extension
Extension Count Extension Count Extension Count
exe 18318271 html 10175562 (no extension) 2813930
dll 2180563 zip 690314 pdf 291078
rar 246302 m2t 183796 gz 82844
jpg 77256 doc 71797 dex 54009
lnk 29421 png 28290 xml 20309
gif 18915 php 18192 xls 17697
fpx 16102 xlsb 12898 swf 11072
sh 4972 pl 4797 rtf 4311
mp3 3619 bmp 3407 chm 2366
docm 2354 xlsm 1827 mp4 1691
riff 1310 mts 1072 asf 836
bz2 762 plist 662 py 645
wmf 608 docx 595 tar 582
ttf 512 ogg 462 xlsx 417
ppt 415 wav 356 tif 339
svg 229 (386) 207 a 207
torrent 145 mov 110 rsrc 101
eps 92 dotm 76 m4a 59
rb 55 xlam 53 webp 49
otf 43 mpg 31 pptx 26
webm 23 acr 21
79
Table 6.2: Selected File Extensions with File Count and Category(Type)
Extension Count Category Extension Count Category
exe 18318271 executable html 10175562 link
(no extension) 2813930 executable dll 2180563 executable
zip 690314 compressed pdf 291078 Adobe
rar 246302 compressed m2t 183796 video
gz 82844 compressed jpg 77256 image
doc 71797 document dex 54009 image
lnk 29421 link png 28290 image
xml 20309 document gif 18915 image
php 18192 script xls 17697 document
fpx 16102 image xlsb 12898 document
swf 11072 image sh 4972 script
pl 4797 script rtf 4311 document
mp3 3619 audio bmp 3407 image
chm 2366 link docm 2354 document
xlsm 1827 document mp4 1691 video
riff 1310 image mts 1072 video
py 645 script docx 595 document
tar 582 compressed ppt 415 document
mov 110 video rb 55 script
80
Table 6.3: Relationship between Types of Malware and File Extensions
File Ext Ad PUA/P Spy Script Trojan Ransom Virus Worm
no ext
bmp
chm
dex
dll
doc
docx
exe
fpx
gif
gz
html
jpg
lnk
m2t
mp3
pdf
php
pl
png
ppt
py
rar
rb
riff
rtf
sh
swf
tar
xls
xml
zip
81
APPENDIX C
MALWARE/FILE TYPE ANALYSIS DATA
82
Table 3.1: Malware File Extension Used in Study
Extension File Description
(no extension) Linux-Dev86 executable headerless
asm assembler source ASCII text
asm assembler source Non-ISO extended-ASCII text
asf Microsoft ASF
elf ELF 32-bit LSB executable Intel 80386 version 1 (SYSV)
dos DOS batch file ASCII text with CRLF line terminators
dos DOS batch file ISO-8859 text
dos DOS executable (COM)
c C source ASCII text
com COM executable for DOS
com COM executable for MS-DOS
dat data
dex Dalvik dex file version 035
dll PE32 executable (DLL) (console) Intel 80386
dll PE32 executable (DLL) (GUI) Intel 80386 for MS Windows
dll PE32 executable (DLL) (native) Intel 80386 for MS Windows
dll PE32+ executable (DLL) (GUI) x86-64 for MS Windows
doc Composite Document File V2 Document Can’t read SSAT
doc Composite Document File V2 Document Little Endian Os
exe PE32 executable (console) Intel 80386 for MS Windows
exe PE32 executable (GUI) Intel 80386 for MS Windows
exe PE32 executable (native) Intel 80386 for MS Windows
exe PE32 executable Intel 80386 for MS Windows
exe PE32+ executable (GUI) x86-64 for MS Windows
gif GIF image data version 89a 10 x 12
gz gzip compressed data from NTFS filesystem (NT)
gz gzip compressed data from Unix
html HTML document ASCII text
html HTML document ISO-8859 text
html HTML document Non-ISO extended-ASCII text
html HTML document UTF-8 Unicode (with BOM)
img DOS/MBR boot sector code offset 0x3c+2 OEM-ID ”MSDOS5.0”
iso ISO-8859 text with CRLF line terminators
iso Non-ISO extended-ASCII text
jar Java archive data (JAR)
java compiled Java class data
jpg JPEG image data JFIF standard 1.01 aspect ratio density 1x1
Continues on next page
83
Extension File Description
ms MS Windows shortcut Item
pas Pascal source ASCII text
pdf PDF document version 1.3
php PHP script ASCII text with CR line terminators
pl perl script ASCII text executable
pl perl script executable (binary data)
png PNG image data 8-bit/color RGBA non-interlaced
rar RAR archive data
rtf Rich Text Format
smgl exported SGML document ASCII text
smtp SMTP mail ASCII text with CRLF line terminators
swf Macromedia Flash data (compressed)
txt ASCII text
txt UTF-8 Unicode text
xls Composite Document File V2 Document Little Endian Os 0
xml XML document text
zip Zip archive data
Table C.1: Malware and Corresponding File Types
Malware Pics Docs Executable PDF Compressed Links Videos
Adware
PUA/PUP
Stego
Ransomware
Script-Based
Spyware
Trojans
Virus
Worms
84
APPENDIX D
COMPONENTS OF THE FRAMEWORK
85
Figure 7.2: Structural: A UML Theory Diagram for the Effects of Malware Analysis in
Reports
86
Figure 7.4: Structural: A UML Class Diagram Illustrating the Structure of the Framework
87
Figure 7.3: Structural: Map of Malware Types with Identified File Types
88
Figure 7.5: Behavioral: Flowchart for Companies Using a Bug-Bounty Platform to Assess
Potential Attack Vectors