GHSA-fqw6-gf59-qr4w
HIGHGHSA-fqw6-gf59-qr4w is a high-severity (CVSS 7.8) Improper Privilege Management vulnerability in github.com/containerd/containerd. O3 Security confirms whether GHSA-fqw6-gf59-qr4w is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
containerd user ID handling bypass allows runAsNonRoot evasion
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-fqw6-gf59-qr4w.
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-fqw6-gf59-qr4w 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 0 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/containerd/containerd🐹github.com/containerd/containerd/v2🐹github.com/containerd/containerd/v2🐹github.com/containerd/containerd/v2Real-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
A bug was found in containerd where containers launched with a numeric User directive that cannot be parsed as a 32-bit integer are incorrectly treated as a username. If a crafted image provides an /etc/passwd file mapping this large numeric string to root, the container ultimately runs as root (UID 0). This allows the Kubernetes runAsNonRoot restriction to be bypassed, causing unexpected behavior for environments that require containers to run as a non-root user.
Patches
This bug has been fixed in the following containerd versions:
- 2.3.1
- 2.2.4
- 2.0.9
- 1.7.32
Note: The containerd 2.1 release has reached its end of life and a fixed version is not provided.
Users should update to these versions to resolve the issue.
Workarounds
Ensure that only trusted images are used and that only trusted users have permissions to import images. Alternatively, enforcing a specific numeric runAsUser in the Kubernetes Pod securityContext overrides the USER directive in the image and prevents the bypass. Newer versions of Kubernetes, starting with 1.34, also appear to enforce runAsNonRoot properly regardless of this bug.
Credits
The containerd project would like to thank Lei Wang (@ssst0n3) for responsibly disclosing this issue in accordance with the containerd security policy.
Resources
- https://github.com/advisories/GHSA-265r-hfxg-fhmg (CVE-2024-40635)
For more information
If there are any questions or comments about this advisory:
- Open an issue in containerd
- Send an email to [email protected]
To report a security issue in containerd:
- Report a new vulnerability
- Send an email to [email protected]
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/containerd/containerd | ≥ 1.7.27&&< 1.7.32 | 1.7.32 |
| 🐹Go | github.com/containerd/containerd/v2 | ≥ 2.0.4&&< 2.0.9 | 2.0.9 |
| 🐹Go | github.com/containerd/containerd/v2 | ≥ 2.1.0-beta.0&&< 2.2.4 | 2.2.4 |
| 🐹Go | github.com/containerd/containerd/v2 | ≥ 2.3.0-beta.0&&< 2.3.1 | 2.3.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/containerd/containerd. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/containerd/containerd to 1.7.32 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-fqw6-gf59-qr4w 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 pinpoints whether GHSA-fqw6-gf59-qr4w is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-fqw6-gf59-qr4w. 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.
Red Hat OpenShift Container Platform and its layered products include the containerd Go library as a build-time dependency for various components. These products do not use containerd as a container runtime; CRI-O is used instead. The vulnerable code path responsible for parsing User directives during container…
Frequently Asked Questions
Is GHSA-fqw6-gf59-qr4w in your dependencies?
O3 detects GHSA-fqw6-gf59-qr4w across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.