BuildKit vulnerable to malicious frontend causing file escape outside of storage root
cve-program · CVE-2026-33747
PublishedBuildKit is a toolkit for converting source code to build artifacts in an efficient, expressive and repeatable manner. Prior to version 0.28.1, 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. The issue has been fixed in v0.28.1. The vulnerability 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.
Read the publisher's advisoryeuvd · EUVD-2026-16518
PublishedBuildKit is a toolkit for converting source code to build artifacts in an efficient, expressive and repeatable manner. Prior to version 0.28.1, 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. The issue has been fixed in v0.28.1. The vulnerability 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.
Read the publisher's advisorynvd · CVE-2026-33747
PublishedBuildKit is a toolkit for converting source code to build artifacts in an efficient, expressive and repeatable manner. Prior to version 0.28.1, 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. The issue has been fixed in v0.28.1. The vulnerability 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.
Read the publisher's advisoryosv · GHSA-4c29-8rgm-jvjj
Published### 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.
Read the publisher's advisoryosv · GO-2026-4858
PublishedBuildKit's Malicious frontend can cause file escape outside of storage root in github.com/moby/buildkit
Read the publisher's advisoryAffected versions, risk and source history
Related advisories and sources
Publishers link these advisories through the identifiers shown below. A shared identifier or date alone does not tell you whether your software is affected or whether the advisories describe the same cause.
CVE-2026-33747 · CVE overview and exploitation status
cve-program · CVE-2026-33747
- https://github.com/moby/buildkit/security/advisories/GHSA-4c29-8rgm-jvjj
- https://github.com/moby/buildkit/releases/tag/v0.28.1
euvd · EUVD-2026-16518
- https://github.com/moby/buildkit/security/advisories/GHSA-4c29-8rgm-jvjj
- https://github.com/moby/buildkit/releases/tag/v0.28.1
nvd · CVE-2026-33747
- https://github.com/moby/buildkit/releases/tag/v0.28.1
- https://github.com/moby/buildkit/security/advisories/GHSA-4c29-8rgm-jvjj
osv · GHSA-4c29-8rgm-jvjj
- https://github.com/moby/buildkit/security/advisories/GHSA-4c29-8rgm-jvjj
- https://nvd.nist.gov/vuln/detail/CVE-2026-33747
- https://github.com/moby/buildkit
- https://github.com/moby/buildkit/releases/tag/v0.28.1