CVE-2025-54867

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

The following advisory appears to be related to this vulnerability:

• https://github.com/advisories/GHSA-vpvm-3wq2-2wvm
• https://github.com/advisories/GHSA-fh74-hm69-rqjw

CVE-2025-54867 has a CVSS score of 7.0 (High). The vector is requires local access, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (0.5.5); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is CVE-2025-54867? CVE-2025-54867 is a high-severity security vulnerability in youki (rust), affecting versions < 0.5.5. It is fixed in 0.5.5.
2. How severe is CVE-2025-54867? CVE-2025-54867 has a CVSS score of 7.0 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of youki are affected by CVE-2025-54867? youki (rust) versions < 0.5.5 is affected.
4. Is there a fix for CVE-2025-54867? Yes. CVE-2025-54867 is fixed in 0.5.5. Upgrade to this version or later.
5. Is CVE-2025-54867 exploitable, and should I be worried? Whether CVE-2025-54867 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2025-54867 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2025-54867? Upgrade youki to 0.5.5 or later.