An exploit can be a program or piece of code, designed to take advantage of vulnerabilities in applications, and this is usually done by cybercriminals with the goal of ultimately installing malware, such as ransomware, launching DDoS attacks or other exploits. For blockchain projects, which are high-value targets for hackers, exploitations have serious implications as these blockchains store and process crypto assets and other valuable information.

And this is what makes exploit development so critical to the safety of digital assets and sensitive information housed on computer systems. Exploit development is essentially the act of finding vulnerabilities in software and applications and establishing how they can be used to overtake a targeted system. This is done by developing an exploit that can take advantage of vulnerabilities such as application security, and the idea is to gain information about potential exploits and address them before cybercriminals can use them against you.

Tools Used by Exploit Developers

Penetration testers who get involved in exploit development typically use a number of tools including system monitoring tools, debuggers, disassemblers, and decompilers. Here we’ll briefly describe the function of each of these to give more context into the work that goes into exploit development.

System Monitoring Tools

System monitoring can enable an exploit developer to identify potential vulnerabilities without performing code analysis or attempting to exploit an application.  System monitoring tools monitor the behavior of an application and can provide deep insight into how it runs and respond to various events. This information can be used to identify vulnerabilities based on how the application behaves in certain scenarios. Some common system monitoring tools include Nagios and Cacti.

Decompilers, Disassemblers and Debuggers

When software is compiled, it is converted from source code to assembly code and then on to machine (binary) code.  Disassemblers and decompilers reverse this process.  A disassembler generates assembly instructions from machine code, making it possible to read and understand what a program is doing.  Decompilers go a step further by attempting to reconstruct a facsimile of the original source code.

Debuggers are tools designed to help debug programs by allowing a developer to pause code execution and inspect the current state of the program’s variables, memory, etc. A handy list of debuggers can be found on Wikipedia here

Disassemblers, decompilers, and debuggers are all useful for exploit development because they make it possible to explore an application and search for vulnerabilities that could then be exploited.

Software Auditing and Finding Vulnerabilities

Before an exploit developer can exploit a vulnerability, they need to know it exists.  The three main ways to do software auditing to find vulnerabilities include:

1) White Box Testing 

White box testing assumes that you have full knowledge and access to all the code and other documents related to an application or piece of code, and it’s typically much faster than a trial and error approach. This is in large part because the exploit developer knows what to test.  However, the exploit developer needs to understand the language in which the application is written to perform white box testing.

2) Black Box Testing

Black box testing is performed with no knowledge of an application’s internals.  The exploit developer interacts with the application just like a user would, entering malformed and malicious inputs into the application in an attempt to identify exploitable vulnerabilities. Black box testing requires no special knowledge of the language in which the application was written but is often slower than white box testing and may miss vulnerabilities.

3) Gray Box Testing

Gray box testing is a middle ground between white box and black box testing.  In a gray box assessment, the attacker has some knowledge of the internal workings of the target application but not complete access to source code like in a white-box assessment.

For more information on black vs gray vs white box testing, check out our article here.

Why Exploit Development Is Critical for Better Cybersecurity

Exploit development is absolutely crucial in today’s fast evolving cybersecurity era. Cybercriminals have become more sophisticated and new attack vectors emerge often. In such an ever-evolving environment, organizations need to actively work to identify and close vulnerabilities before they can be exploited by an attacker.  

Exploit development is a useful tool in this process because it helps to build understanding about how a particular vulnerability works and to validate that a patch for vulnerability actually mitigates the threat. So if you want to learn more about exploit development and how to implement it into your security strategies, be sure to reach out to our cybersecurity experts at halborn@protonmail.com

Rob Behnke
02.18.2022