What is SAST Testing

What is SAST Testing#

What is Static Application Security Testing (SAST)?#

Static security testing, also known as Static Application Security Testing (SAST),is a security methodology that analyzes an application’s source code and related artifacts (such as design documents) without executing the code. The purpose is to identify potential security weaknesses before developing or running the application.

For Python applications, specific Python SAST tools perform an in-depth, automated review of the source code to detect security weaknesses and potential vulnerabilities early in the development lifecycle.

SAST testing is a “white-box” testing approach because it analyzes the application’s internal structure, typically by examining the code directly. Dynamic application testing is more complex and often only sensible within the target context where an application will run! For dynamic application testing so called fuzzers are used.

How SAST works on Python Code#

The primary advantage of SAST for Python is automation. SAST tools automatically scan the code’s structure, data flow, and control flow without executing the code. The characteristics of transparent open Python SAST tools are:

  • Objective: The specific function calls that can lead to security problems are transparent. So it is completely transparent what rules are used to check the Python code on weaknesses. Mind that when a property and/or AI solution is used it is often completely unknown what rules are used. And the bad news is: Most commercial tools have a very limited set of rules!

  • Human Role: While scanning is automated, human intelligence is crucial for reviewing the findings. A human developer or security analyst must determine the context where the program will be used and decide if the vulnerability requires fixing.

  • Limitation: No single tool, even one powered by AI, can definitively know the exact environment or business context in which the Python code runs. Therefore, fully automating the fix process is generally undesirable. While AI can suggest and even generate fixes, only a human developer or security professional can accurately weigh the development costs against the actual security risks and confirm that the change won’t introduce new functional bugs or operational failures.

Overview of SAST testing for Python

Important

Automated SAST testing is only possible for Python code — and Python Code Audit is your best ally for automating this process.

However, a thorough security review of your architecture, design, and requirements is just as important! These areas demand specialized security knowledge and experience. The same expertise is often needed to properly address the vulnerabilities identified in your code.

If you need support, consider reaching out to one of our sponsors — they may be able to help you with this task!

Tip

To learn WHY SAST testing for Python code is crucial, check the section Why Security Testing!