Common LLM App Security Failures and Safe Testing Methods

Dev Community advises teams to actively test their LLM applications for security vulnerabilities rather than just checking response quality. The article outlines five common failure points, including prompt injection and system prompt leakage. It recommends using harmless unique markers called "canaries" to safely test for control failures in staging environments. The canary method provides clear, binary results and leaves traceable evidence in logs. The author provides practical testing harness examples and remediation guidance for each vulnerability type.