GHSA-4vrq-3vrq-g6gg — buildkit
HIGHGHSA-4vrq-3vrq-g6gg is a high-severity (CVSS 7.5) Path Traversal vulnerability in github.com/moby/buildkit. A fix is available for github.com/moby/buildkit — see the affected versions and patch details below.
BuildKit Git URL subdir component can cause access to restricted files
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-4vrq-3vrq-g6gg.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-4vrq-3vrq-g6gg plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,156 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
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
BuildKit is a toolkit for converting source code to build artifacts in an efficient, expressive and repeatable manner. Prior to version 0.28.1, insufficient validation of Git URL fragment subdir components may allow access to files outside the checked-out Git repository root. Possible access is limited to files on the same mounted filesystem. The issue has been fixed in version v0.28.1 The issue affects only builds that use Git URLs with a subpath component. As a workaround, avoid building Dockerfiles from untrusted sources or using the subdir component from an untrusted Git repository where the subdir component could point to a symlink.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/moby/buildkit | all versions | 0.28.1go get github.com/moby/buildkit@v0.28.1 |
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 0.28.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4vrq-3vrq-g6gg is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-4vrq-3vrq-g6gg can be triaged on real exposure rather than presence alone.
Tailored to GHSA-4vrq-3vrq-g6gg. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
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 |
|---|---|---|
| multicluster engine for Kubernetes 2.1 | multicluster-engine/must-gather-rhel9:1784849867 | RHSA-2026:46885 |
| multicluster engine for Kubernetes 2.1 | multicluster-engine/must-gather-rhel9:1784849867 | RHSA-2026:47388 |
| multicluster engine for Kubernetes 2.8 | multicluster-engine/must-gather-rhel9:1782158798 | RHSA-2026:30650 |
| OpenShift API for Data Protection 1.3 | oadp/oadp-mustgather-rhel9:1785177359 | RHSA-2026:51033 |
| OpenShift API for Data Protection 1.4 | oadp/oadp-mustgather-rhel9:1779770049 | RHSA-2026:29854 |
| OpenShift API for Data Protection 1.5 | oadp/oadp-mustgather-rhel9:1779770057 | RHSA-2026:26568 |
| Red Hat Openshift Data Foundation 4.20 | odf4/cephcsi-rhel9:1786627460 | RHSA-2026:57013 |
| Red Hat Openshift Data Foundation 4.22 | odf4/cephcsi-rhel9:1782932114 | RHSA-2026:37387 |
Frequently Asked Questions
Is GHSA-4vrq-3vrq-g6gg in your dependencies?
O3 Security finds GHSA-4vrq-3vrq-g6gg across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.