Static Application Security Testing, or SAST, is a method of examining source code, bytecode, or other application artifacts before the software runs. It looks for insecure patterns such as injection risks, unsafe input handling, hardcoded secrets, and logic flaws that can be found by analysis rather than execution. Because it runs early in the development cycle, SAST helps teams catch problems before release, when fixes are cheaper and easier to verify.
SAST matters in cyber security because attackers often exploit weaknesses that were present in the code long before deployment. In defense, it is used in build pipelines, code review workflows, and developer tools to surface risk automatically. Its value depends on signal quality: too many false positives create alert fatigue, while weak coverage can miss real issues. Effective SAST programs use tuning, triage, and workflow integration so teams can focus on findings that are actually reachable and worth fixing.