When to use SAST versus an LLM security scanner

This post introduces a comparative analysis of SAST and LLM-based security scanners, advocating for their complementary use. It details the trade-offs in cost, consistency, audit evidence, vulnerability types, and finding validation between deterministic SAST and probabilistic LLM scanners. The post recommends SAST for continuous, per-commit scanning due to its predictable cost and auditability, and LLM scanners for merge-request-level reasoning to catch business logic flaws and validate findings. It highlights that LLM scanners can generate working exploits to validate findings, reducing false positives.