Fuzz Testing

Introduction to What is Fuzz Testing?

Fuzz Testing is considered the type of testing wherein either automated, or semi-automated testing techniques are required to find out errors in coding and the loopholes in security in either software or the operating systems by providing the input of the random data to the system. This random data is called FUZZ. After all, this takes place, the system is checked for different types of exceptions like either system getting crashed down, or even the built-in code gets failed and much more. This was originally developed by someone called Barton Miller, who was from the University of Wisconsin. It is also called fuzzing is considered to be the type of security testing.

Why do we Need Fuzz Testing?

• Often, Fuzz testing has the capability to figure out the most serious security faults in the system.
• It provides much more effective results when we use it along with Black Box Testing, Beta Testing, or different debugging methods.
• It is also needed to verify the vulnerability of the software. It is also a really cost-effective testing technique.
• It is considered to be one black box testing technique. It is also one of the most used method hackers that finds the vulnerability of the system.

How is Fuzzy Testing Performed?

The steps for fuzzy testing include the basic testing steps:

• Step 1: Recognition of the target system.
• Step 2: Recognition of the inputs.
• Step 3: Fuzzed data Generation.
• Step 4: Test Execution using fuzzy data.
• Step 5: System behavior Monitoring.
• Step 6: Logging of defects.

Examples of Fuzzers

There are many fuzzers as below:

• Mutation-Based Fuzzers: These fuzzers change the data samples existing to make fresh test data. This is quite easy as well as the direct method; it starts along with reasonable protocol and keeps mingling each and every byte or even as a file.
• Generation-Based Fuzzers: They define data that is new depending upon the model input. It starts input generation from scratch depending upon the specification.
• Protocol-Based Fuzzer: It is considered fuzzer that is most successful and has quite explained knowledge regarding the protocol format that has to be tested. This understanding is dependent upon specification. It includes the writing of an array of specifications inside the tool and, after that, makes use of the model-based technique. It is also known as syntax testing or grammar testing, or robustness testing.

We have got two limitations of this protocol-based fuzzing that is as under:

• We cannot proceed with testing until and unless the specification is quite mature.
• There exist many protocols that are an extension of the published protocols. In case fuzz testing is based on these specifications, which are published, then test coverage for these new protocols would get limited.

There is the simplest form of fuzzing testing, which is sending random input into the software in the form of protocol packets or even in the form of an event. This particular way of passing random input is considered quite powerful for locating bugs in various applications and services. There are other techniques also that are available, and also they are quite easy to implement.

Bug Types Detected by Fuzz Testing

Following are the bug types detected by fuzz testing:

• Memory Leaks and Assertion Failures: This method is vastly used in wide applications wherein bugs affect memory safety, which is considered a severe vulnerability.
• Invalid Input: Fuzzers are needed to generate the invalid input required to test the error-handling routines in fuzz testing. Also, it is quite necessary for software that doesn’t control the input. Fuzzing is considered to be a way of automating negative testing.
• The correctness of Bugs: Fuzzing is needed for detecting few kinds of “correctness” bugs like a corrupted database or poor search results, and much more.

Fuzz Testing Tools

The tools that are quite useful in web security can also largely be used in fuzz testing or fuzzy, for Example, Peach Fuzzer, Burp Suite, etc.

1. Peach Fuzzer

This tool gives much more robust as well as security coverage as compared to the scanner. If we talk about other testing tools, they, however, have the capability to search only the known threats. But Peach Fuzzer makes users discover known as well as unknown threats.

2. Spike Proxy

Spike is considered to be the tool of professional-grade that searches for vulnerabilities at the application level in various web applications. SPIKE Proxy considers only the basics like SQL Injection or cross-site scripting. However, it is fully an open infrastructure of Python. SPIKE Proxy is present for both Linux and Windows.

Advantages and Disadvantages

Given below are the advantages and disadvantages mentioned:

Advantages:

• Bugs discovered in fuzz testing are often considered severe, and mostly, it is used by the hackers that consist of crashes, memory leak or an unhandled exception, and much more.
• If any error or bug gets failed to be discovered by the testers because of the limitation of time as well as resources, then those bugs can be discovered in Fuzz testing.

Disadvantages:

• All alone, fuzz testing alone does not have the ability to give the overall scenario of all the security threats.
• Also, fuzz testing is considered to be not really effective when dealing with security bugs that don’t cause program crashes like viruses, worms, etc.
• It has the capability to detect only simple threats.
• In order to give an effective performance, it requires significant time.

Conclusion

Thus we can conclude that in software engineering, this testing, that is, Fuzz testing demonstrates the presence of the bugs in any application. This testing does not ensure bug detection in a complete manner in any of the applications. However, if we use this Fuzz technique, it guarantees that the application is quite robust as well as secure, the reason being that fuzz testing helps quite much in exposing many common vulnerabilities.

Recommended Articles

This is a guide to Fuzz Testing. Here we discuss what fuzz testing is? testing tools, advantages, and disadvantages, respectively. You can also go through our other suggested articles to learn more –

1. Benchmark Testing
2. Types of Software Testing
3. What is Usability Testing?
4. Static Testing