CVE-2026-33747

BuildKit vulnerable to malicious frontend causing file escape outside of storage root

Published Mar 27, 2026 CVSS 3.1 · 8.4 High EPSS < 1% KEV · Not listed
Description
BuildKit 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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Debian DSA Debian DSA DSA-6443-1 docker.io security update
Github GHSA Github GHSA GHSA-4c29-8rgm-jvjj BuildKit's Malicious frontend can cause file escape outside of storage root
Ubuntu USN Ubuntu USN USN-8230-1 Docker vulnerabilities
History
Type Values Removed Values Added
First Time appeared Mobyproject
Mobyproject buildkit
CPEs cpe:2.3:a:mobyproject:buildkit:*:*:*:*:*:*:*:*
Vendors & Products Mobyproject
Mobyproject buildkit
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Moby
Moby buildkit
Vendors & Products Moby
Moby buildkit
Type Values Removed Values Added
Description BuildKit 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.
Title BuildKit vulnerable to malicious frontend causing file escape outside of storage root
Weaknesses CWE-22
References
Metrics cvssV3_1

{'score': 8.4, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Mar 27, 2026, 7:59 PM
Reserved
Mar 23, 2026, 6:30 PM
Status
Analyzed
Published
Mar 27, 2026, 1:16 AM
Modified
Jun 17, 2026, 10:38 AM
Severity
Moderate
Public date
Mar 27, 2026, 12:49 AM