# CVE-2026-121541: Docker Buildx entitlements bypass in multi-target builds

Source: https://junglewise.ai/threats/cve-2026-121541-in-docker-buildx-versions-v0-19-0-through-v0-38-0-an-untrusted  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-03. Updated: 2026-11-03  
License: CC BY 4.0 with a link back

CVE-2026-121541 · Severity: info · Published 2026-11-03

Docker Buildx is a build tool that executes container build definitions with security controls to prevent access to sensitive files. In versions v0.19.0 through v0.38.0, an attacker can craft a malicious multi-target build definition that bypasses these file access controls, potentially exposing files on the build system to an untrusted build process. Users running untrusted build definitions are at risk of unauthorized file disclosure.

Technologies: [Docker Buildx](https://junglewise.ai/threats/technologies/buildx). Vendors: [Docker](https://junglewise.ai/threats/vendors/docker).

## Quick answers

**Is CVE-2026-121541 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-121541 being exploited in the wild.

**How severe is CVE-2026-121541?** Informational severity, published 3 November 2026.

**Which products and versions are affected?** Docker Buildx v0.19.0 through v0.38.0.

**Is there a fix for CVE-2026-121541?** Yes: fixed in v0.38.1. Until then: Run only trusted Bake definitions until upgrading. Audit Bake definitions to ensure they do not contain suspicious paths outside of trusted directories. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-121541 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-121541?** Check whether you run Docker Buildx at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Fixed in v0.38.1

Run only trusted Bake definitions until upgrading. Audit Bake definitions to ensure they do not contain suspicious paths outside of trusted directories.

## Technical details

An entitlements verification bypass exists in Docker Buildx's Bake build system for multi-target builds, where filesystem paths in certain targets are not properly validated against approved fs.read entitlements. The vulnerability allows an untrusted Bake definition to access files accessible to the Buildx client without proper authorization checks. The issue is patched in v0.38.1.

## Affected products

- Docker Buildx v0.19.0 through v0.38.0

## Timeline

- 2026-11-03: disclosed

## References

- [https://github.com/docker/buildx/security/advisories/GHSA-xg6v-cv2h-2w5h](https://github.com/docker/buildx/security/advisories/GHSA-xg6v-cv2h-2w5h)

## Related threats

- [Docker Buildx filesystem entitlement bypass in Bake](https://junglewise.ai/threats/cve-2026-121542-in-docker-buildx-versions-v0-19-0-through-v0-38-0-an-untrusted)
- [Docker Buildx bake entitlement consent bypass with --progress=rawjson](https://junglewise.ai/threats/cve-2026-93325-buildx-bake-requires-the-user-to-grant-entitlements-with-allow-or)
- [Docker Buildx Bake fs.read approval bypass for filesystem inputs](https://junglewise.ai/threats/cve-2026-103433-docker-buildx-bake-does-not-request-the-expected-fs-read)