Container Security Scanning

Container security scanning analyzes Docker images for known vulnerabilities (CVEs) in OS packages and application dependencies, misconfigurations in Dockerfiles, embedded secrets (API keys, passwords), and compliance violations. This is a critical gate in the CI/CD pipeline that prevents deploying images with known security issues to production.

Scanning tools like Trivy, Grype, Snyk Container, and AWS ECR native scanning compare packages in the image against vulnerability databases (NVD, OS vendor advisories, GitHub Security Advisories). Scans should be performed at multiple points: during CI/CD (blocking builds with critical/high vulnerabilities), in the container registry (continuous scanning as new CVEs are disclosed), and at admission time in Kubernetes (using admission controllers like Kyverno or OPA Gatekeeper to block unscanned or vulnerable images).

Effective container security goes beyond vulnerability scanning: use minimal base images to reduce attack surface, run as non-root, set the filesystem to read-only where possible, drop unnecessary Linux capabilities, enable seccomp and AppArmor profiles, and sign images with cosign for supply chain integrity. Vulnerability findings should be prioritized based on CVSS score, exploitability, and whether the vulnerable package is actually reachable in the running application. A practical approach is to fail builds only on critical/high severity with a known fix available, while tracking medium/low findings for scheduled remediation.