Buildkit credentials inlined to Git URLs could end up in provenance attestationGHSA-gc89-7gcr-jxqc
MEDIUMFix: moby/buildkit@75123c6GHSA-gc89-7gcr-jxqc is a medium-severity (CVSS 6.5) Information Exposure vulnerability in github.com/moby/buildkit. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for github.com/moby/buildkit — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-gc89-7gcr-jxqc.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
github.com/moby/buildkitReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
When the user sends a build request that contains a Git URL that contains credentials and the build creates a provenance attestation describing that build, these credentials could be visible from the provenance attestation.
Git URL can be passed in two ways:
- Invoking build directly from a URL with credentials.
buildctl build --frontend dockerfile.v0 --context https://<credentials>@url/repo.git
Equivalent in docker buildx would be
docker buildx build https://<credentials>@url/repo.git
- If the client sends additional VCS info hint parameters on builds from a local source. Usually, that would mean reading the origin URL from
.git/configfile.
Thanks to Oscar Alberto Tovar for discovering the issue.
Impact
When a build is performed under specific conditions where credentials were passed to BuildKit they may be visible to everyone who has access to provenance attestation.
Provenance attestations and VCS info hints were added in version v0.11.0. Previous versions are not vulnerable.
In v0.10, when building directly from Git URL, the same URL could be visible in BuildInfo structure that is a predecessor of Provenance attestations. Previous versions are not vulnerable.
Note: Docker Build-push Github action builds from Git URLs by default but is not affected by this issue even when working with private repositories because the credentials are passed with build secrets and not with URLs.
Patches
Bug is fixed in v0.11.4 .
Workarounds
It is recommended to pass credentials with build secrets when building directly from Git URL as a more secure alternative than modifying the URL.
In Docker Buildx, VCS info hint can be disabled by setting BUILDX_GIT_INFO=0. buildctl does not set VCS hints based on .git directory, and values would need to be passed manually with --opt.
References
- Inline credentials in URLs deprecated in RFC3986 https://www.rfc-editor.org/rfc/rfc3986#section-3.2.1
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/moby/buildkit | ≥ 0.10.0&&< 0.11.4 | 0.11.4go get github.com/moby/buildkit@v0.11.4 |
Affected Products
buildkitmobyprojectResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/moby/buildkit, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/moby/buildkit to 0.11.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-gc89-7gcr-jxqc is resolved across your whole dependency graph.
Workarounds
Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat OpenShift Container Platform 4.13 | openshift4/ose-docker-builder:v4.13.0-202306050632.p0.gd02643e.assembly.stream | RHSA-2023:3537 |
| Red Hat OpenShift Service Mesh 2.4 for RHEL 8 | openshift-service-mesh/grafana-rhel8:2.4.4-2 | RHSA-2023:5952 |
Frequently Asked Questions
Is GHSA-gc89-7gcr-jxqc in your dependencies?
Find it across Go, including transitive dependencies.