CVE-2026-33748: BuildKit Git URL subdir component can cause access to restricted files

March 26, 2026 (updated April 24, 2026)

Insufficient validation of Git URL fragment subdir components (<url>#<ref>:<subdir>, docs) may allow access to files outside the checked-out Git repository root. Possible access is limited to files on the same mounted filesystem.

References

docs.docker.com/build/concepts/context/
github.com/advisories/GHSA-4vrq-3vrq-g6gg
github.com/moby/buildkit
github.com/moby/buildkit/releases/tag/v0.28.1
github.com/moby/buildkit/security/advisories/GHSA-4vrq-3vrq-g6gg
nvd.nist.gov/vuln/detail/CVE-2026-33748

Code Behaviors & Features

Detect and mitigate CVE-2026-33748 with GitLab Dependency Scanning

Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Learn more about Dependency Scanning →