Container Security Testing: Docker, Images, and Runtime Protection

Image Security Testing

Container image testing evaluates base image provenance (trusted registries vs public sources), known CVE scanning (OS packages, application dependencies), image signing and verification, minimal image construction (unnecessary packages expand attack surface), and Dockerfile best practices (multi-stage builds, non-root users, read-only layers).

Runtime Configuration Testing

Runtime testing evaluates whether containers run as non-root, whether privileged mode is disabled, whether capability dropping is implemented, whether read-only root filesystems are enforced, and whether resource limits prevent denial-of-service. Each unnecessary privilege is a potential escape vector.

Registry Security

Testing evaluates registry access controls, image pull policies, vulnerability scanning integration, and whether unsigned or unscanned images can be deployed to production.

Container Escape Vectors

Testing probes for escape vectors: privileged containers, host namespace sharing, writable Docker socket mounts, kernel vulnerability exploitation, and misconfigured seccomp/AppArmor profiles. Container escape is the highest-severity finding in container security.

Testing with Penetrify

Penetrify's container security testing covers image analysis, runtime configuration, registry security, and escape vector testing—providing the complete container security assessment that compliance frameworks require.