GHSA-4c29-8rgm-jvjj (CVE-2026-33747)

Details

Impact

When using a custom BuildKit frontend, the frontend can craft an API message that causes files to be written outside of the BuildKit state directory for the execution context.

Patches

The issue has been fixed in v0.28.1+

Workarounds

Issue requires using an untrusted BuildKit frontend set with #syntax or --build-arg BUILDKIT_SYNTAX. Using these options with a well-known frontend image like docker/dockerfile is not affected.

Affected Packages

github.com/moby/buildkit

Go

Fixed in:

0.28.1

References

ADVISORY

https://github.com/advisories/GHSA-4c29-8rgm-jvjj

PACKAGE

https://github.com/moby/buildkit

WEB

https://github.com/moby/buildkit/releases/tag/v0.28.1

WEB

https://github.com/moby/buildkit/security/advisories/GHSA-4c29-8rgm-jvjj

ADVISORY

https://nvd.nist.gov/vuln/detail/CVE-2026-33747