OWASP ServerlessGoat vs FunctionShield: 2026 Comparison
OWASP ServerlessGoat is a free serverless security tool. FunctionShield is a free serverless security tool. Compare features, ratings, integrations, and community reviews side by side to find the best serverless security fit for your security stack.
CST VerdictBased on our analysis of available product data, here is our conclusion:
DevSecOps teams building serverless functions on AWS Lambda or Google Cloud Functions should use OWASP ServerlessGoat to train developers on the specific attack surface their code introduces: environment variable injection, overprivileged IAM roles, and insecure deserialization in event handlers. The 328 GitHub stars and OWASP backing mean you're learning from battle-tested scenarios, not theoretical ones. This is a teaching tool, not a continuous scanning platform, so skip it if you need automated detection wired into your CI/CD pipeline; use it first to understand what your real scanners should be catching.
Developers building on AWS Lambda or Google Cloud Functions who need to lock down function behavior at runtime should start with FunctionShield; it enforces strict allowlists for system calls, file access, and network connections directly in your code rather than relying on perimeter controls. The free, open-source model (40 GitHub stars, no licensing friction) means you can pilot it in staging without procurement delays. Skip this if you're looking for detection and forensics after a breach; FunctionShield is prevention-only, which is either exactly what you want or a deal-breaker depending on your threat model.
