Open Source Vulnerability Scanners: 13 Free Tools by Category (2026)
A practical guide to free and open source vulnerability scanners, organized by what they scan: code (Semgrep, CodeQL, Bandit, Brakeman), dependencies and containers (OSV-Scanner, Trivy, Grype), secrets (Gitleaks, TruffleHog), web apps (ZAP, Nuclei) and networks (Nmap, OpenVAS). Licenses checked, commands included, limits explained.