GHSA-j26p-6wx7-f3pw is a high-severity (CVSS 7) CWE-61 vulnerability in youki. A fix is available for youki — see the affected versions and patch details below.
Youki: If /proc and /sys in the rootfs are symbolic links, they can potentially be exploited to gain access to the host root filesystem.
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-j26p-6wx7-f3pw.
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-j26p-6wx7-f3pw 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
youkiReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
Summary
If /proc and /sys in the rootfs are symbolic links, they can potentially be exploited to gain access to the host root filesystem.
Details
For security reasons, container creation should be prohibited if /proc or /sys in the rootfs is a symbolic link.
I verified this behavior with youki.
When /proc or /sys is a symbolic link, runc fails to create the container, whereas youki successfully creates it.
This is the fix related to this issue in runc.
- https://github.com/opencontainers/runc/pull/3756
- https://github.com/opencontainers/runc/pull/3773
- https://github.com/opencontainers/runc/blob/main/libcontainer/rootfs_linux.go#L590
- https://github.com/opencontainers/runc/blob/main/tests/integration/mask.bats#L60
Impact
The following advisory appears to be related to this vulnerability:
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | youki | all versions | 0.5.5cargo update -p youki --precise 0.5.5 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for youki, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update youki to 0.5.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-j26p-6wx7-f3pw 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-j26p-6wx7-f3pw can be triaged on real exposure rather than presence alone.
Tailored to GHSA-j26p-6wx7-f3pw. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-j26p-6wx7-f3pw in your dependencies?
O3 Security finds GHSA-j26p-6wx7-f3pw across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.