GHSA-5vpc-35f4-r8w6 is a high-severity (CVSS 8.6) Improper Privilege Management vulnerability in github.com/containers/buildah. A fix is available for github.com/containers/buildah — see the affected versions and patch details below.
Buildah allows build breakout using malicious Containerfiles and concurrent builds
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- 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-5vpc-35f4-r8w6.
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-5vpc-35f4-r8w6 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 377,636 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/containers/buildah🐹github.com/containers/buildah🐹github.com/containers/buildah🐹github.com/containers/buildahReal-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
Impact
With careful use of the --mount flag in RUN instructions in Containerfiles, and by using either multi-stage builds with use of concurrently-executing build stages (e.g., using the --jobs CLI flag) or multiple separate but concurrently-executing builds, a malicious Containerfile can be used to expose content from the build host to the command being run using the RUN instruction. This can be used to read or write contents using the privileges of the process which is performing the build. When that process is a root-owned podman system service which is provided for use by unprivileged users, this includes the ability to read and write contents which the client should not be allowed to read and write, including setuid executables in locations where they can be later accessed by unprivileged users.
Patches
Patches have been merged to the main branch, and will be added to upcoming releases on the release-1.38, release-1.37, release-1.35, and release-1.33 branches.
This addressed a number of Jira cards, but primarily https://issues.redhat.com/browse/RHEL-67616 and https://issues.redhat.com/browse/RHEL-67618, which were then vendored into Podman and backported into olde rbranches.
Workarounds
Mandatory access controls should limit the access of the process performing the build, on systems where they are enabled.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/containers/buildah | ≥ 1.38.0&&< 1.38.1 | 1.38.1go get github.com/containers/buildah@v1.38.1 |
| 🐹Go | github.com/containers/buildah | ≥ 1.37.0&&< 1.37.6 | 1.37.6go get github.com/containers/buildah@v1.37.6 |
| 🐹Go | github.com/containers/buildah | ≥ 1.35.0&&< 1.35.5 | 1.35.5go get github.com/containers/buildah@v1.35.5 |
| 🐹Go | github.com/containers/buildah | all versions | 1.33.12go get github.com/containers/buildah@v1.33.12 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/containers/buildah, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/containers/buildah to 1.38.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-5vpc-35f4-r8w6 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-5vpc-35f4-r8w6 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-5vpc-35f4-r8w6. 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.
This vulnerability marked as important severity rather than moderate because it allows a malicious Containerfile to exploit the `--mount` flag in `RUN` instructions to directly interact with the build host's filesystem. By leveraging this, an attacker can gain unauthorized access to sensitive files or inject malicious…
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux 8 | container-tools:rhel8-8100020250124120243.afee755d | RHSA-2025:1372 |
| Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | container-tools:rhel8-8060020250203202123.3b538bd8 | RHSA-2025:1207 |
| Red Hat Enterprise Linux 8.8 Extended Update Support | container-tools:rhel8-8080020250207173112.0f77c1b7 | RHSA-2025:1275 |
| Red Hat Enterprise Linux 9 | podman-4:5.2.2-13.el9_5 | RHSA-2025:0922 |
| Red Hat Enterprise Linux 9 | buildah-2:1.37.6-1.el9_5 | RHSA-2025:0923 |
| Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions | podman-2:4.2.0-6.el9_0 | RHSA-2025:1186 |
| Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions | buildah-1:1.26.9-1.el9_0 | RHSA-2025:1187 |
| Red Hat Enterprise Linux 9.2 Extended Update Support | buildah-1:1.29.5-1.el9_2 | RHSA-2025:1295 |
Frequently Asked Questions
Is GHSA-5vpc-35f4-r8w6 in your dependencies?
O3 Security finds GHSA-5vpc-35f4-r8w6 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.