Fuzzing, or fuzz testing, isn't actually a new technique. It was developed back in 1989 at the University of Wisconsin-Madison...
By submitting your email address, you agree to receive emails regarding relevant topic offers from TechTarget and its partners. You can withdraw your consent at any time. Contact TechTarget at 275 Grove Street, Newton, MA.
by Professor Barton Miller. With today's focus on developing more secure software, fuzzing has become a more widely used and acknowledged code-testing method.
During the fuzzing process, a program is bombarded with random data, called fuzz. If the program fails to cope with any of this data and begins to crash, lock up, consume memory or produce uncontrolled errors, the developer knows that there is a flaw somewhere within the code. The flaw can then be located and rectified before the program is released or deployed, thus keeping a possible vulnerability out of the final release version. Fuzzing has been frequently used to uncover buffer overflows, which occur when the number of input characters exceeds the available buffer space.
Software programs have several input possibilities, like mice, keyboards and screen devices. Other inputs include calls from other programs or controllers embedded in the actual system. Fuzzing effectively finds bugs because the data entered into a program is random and therefore not constrained by any preconceptions about how the software should behave. When people test software themselves, they may make assumptions about how the software will be used, causing certain input permutations to be overlooked.
A thorough fuzz test uses a combination of valid test data and random fuzz data. The valid data prevents an application from rejecting the information before it can reach a defective piece of code.
You must be aware, though, that passing a fuzz test doesn't make a program bug-free. Fuzzing only allows the simulation of a random, limited sample of a program's behavior. The tests may only show that the software can handle exceptions without crashing. Also, fuzzing doesn't test for logical flaws that can be exploited.
A big advantage of fuzz testing is its cost effectiveness; the testing is usually automated and easy to set up. It is a useful testing method, but it should be used as one of several software-testing methods. Static analysis, peer review and secure coding methodologies should all be a part of any secure software development process.
Dig Deeper on Vulnerability Risk Assessment
Related Q&A from Michael Cobb
Amazon disabled native encryption capabilities in the latest Fire OS version. Expert Michael Cobb explains what this means for security, and if ...continue reading
A pirated app called Happy Daily English beat Apple's App Store security review. Expert Michael Cobb explains how it works and what security teams ...continue reading
The Lenovo SHAREit file-sharing app has a hardcoded password vulnerability, among other issues. Expert Michael Cobb explains these flaws and how to ...continue reading
Have a question for an expert?
Please add a title for your question
Get answers from a TechTarget expert on whatever's puzzling you.