# CVE-2026-93322: BuildKit daemon panic from malformed LLB merge definition

Source: https://junglewise.ai/threats/cve-2026-93322-a-malicious-frontend-can-submit-an-llb-definition-that-causes  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-05. Updated: 2026-10-05  
License: CC BY 4.0 with a link back

CVE-2026-93322 · Severity: info · Published 2026-10-05

BuildKit is a toolkit used to build container images. A malicious build definition submitted through an untrusted external frontend can crash the BuildKit daemon, halting all builds running on that system. This is a denial-of-service attack that does not compromise data confidentiality or integrity.

Technologies: [Moby BuildKit](https://junglewise.ai/threats/technologies/moby-buildkit). Vendors: [Moby](https://junglewise.ai/threats/vendors/moby).

## Quick answers

**Is CVE-2026-93322 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-93322 being exploited in the wild.

**How severe is CVE-2026-93322?** Informational severity, published 5 October 2026.

**Which products and versions are affected?** Moby BuildKit <=v0.33.0.

**Is there a fix for CVE-2026-93322?** Yes: fixed in v0.33.1. Until then: Avoid using external BuildKit frontends from untrusted sources. Dockerfile builds are not affected by this vulnerability. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-93322 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-93322?** Check whether you run Moby BuildKit 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 v0.33.1

Avoid using external BuildKit frontends from untrusted sources. Dockerfile builds are not affected by this vulnerability.

## Technical details

A crafted LLB (Low Level Build) definition with a malformed MergeOp can trigger a panic in buildkitd. The attack requires a malicious frontend to submit the crafted definition; Dockerfile builds are unaffected. This is a local attack vector with no privilege requirements, causing only availability impact through daemon termination.

## Affected products

- Moby BuildKit <=v0.33.0

## Timeline

- 2026-09-30: disclosed
- 2026-09-30: patched: v0.33.1 released

## References

- [https://github.com/moby/buildkit/releases/tag/v0.33.1](https://github.com/moby/buildkit/releases/tag/v0.33.1)
- [https://github.com/moby/buildkit/security/advisories/GHSA-cv6p-7w7g-xjwq](https://github.com/moby/buildkit/security/advisories/GHSA-cv6p-7w7g-xjwq)

## Related threats

- [Moby BuildKit arbitrary extended attribute setting](https://junglewise.ai/threats/cve-2026-121520-in-buildkit-versions-prior-to-v0-34-1-a-malicious-client-with)
- [Moby BuildKit Git source resolver panic](https://junglewise.ai/threats/cve-2026-121522-in-buildkit-versions-v0-26-0-through-v0-34-1-a-specific-build)
- [Moby BuildKit malformed LLB merge operation denial of service](https://junglewise.ai/threats/cve-2026-93321-a-malicious-frontend-can-submit-an-llb-definition-that-causes)
- [Moby BuildKit proxy CA cleanup disruption](https://junglewise.ai/threats/cve-2026-93315-when-proxy-networking-with-ca-injection-is-enabled-a-build-can)
- [Moby BuildKit Git source policy validation bypass](https://junglewise.ai/threats/cve-2026-93326-a-build-step-for-a-git-source-crafted-in-a-specific-way-can)