Buffer Overflow: A Classic Bug That Continues to be a Problem
Year after year, buffer overflows have been a major source of software security issues, and they remain a top vulnerability in 2019. In fact, the recent well-documented WhatsApp security incident was the result of a buffer overflow vulnerability.
What is a Buffer Overflow?
A buffer overflow is a common software vulnerability. Also known as a buffer overrun, this security issue is serious because it exposes systems to potential cyber threats and attacks.
The software vulnerability happens when there is excess data in a buffer which causes the “overflow”. The extra data then overruns into adjacent storage. When this type of security issue occurs, it can cause a full system crash.
Coding mistakes are the most common cause of buffer overflow vulnerabilities. When a developer fails to create enough buffer space during application development the software is at risk of buffer overrun. Also, DevOps teams often neglect to cross-check for buffer space issues prior to launch.
How to Prevent a Buffer Overflow Attack
One way to completely prevent buffer overflow attacks is to use a coding language that doesn’t allow for them. For example, C is a primary target for buffer attacks because the language enables the vulnerability through direct access to memory. On the other hand, languages like Java, Python, and .NET, are immune from buffer vulnerabilities.
Another way to prevent buffer overflows is to be aware of buffer usage during development. Where buffers are accessed is where the vulnerabilities will occur, especially if the functions deal with user-generated input.
Other best practices for preventing the software vulnerability include:
- Leveraging automated code review and testing.
- DevOps training on the concepts of using unsafe functions.
- A focus on safe functions like strncpy vs strcpy and strncat vs strcat.
- Keeping application servers patched.
- Using code analysis tools to periodically check applications for buffer overflow flaws.
Why Source Code Analysis is the Best Solution for Buffer Overflow Attacks
To absolutely ensure your application is safe from damaging buffer overflow attacks, the best course of action is to use static code analysis (SCA). As mentioned, C and C++ is particularly vulnerable to buffer overflow threats. To protect C and C++ applications, DevOps can use a SCA tool and run a compliance taxonomy like MISRA or CERT to identify software vulnerabilities.
Static code analysis tools are important for detecting security vulnerabilities across software applications. With SCA tools, security vulnerability issues can be found as code is being developed.
If your organization wants proactive protection against security threats like buffer overflow, a static code analysis tool like Klocwork can help. We offer a free trial so you can explore the benefits of Klocwork for yourself.