CVE-2025-54867
Youki Symlink Following Vulnerability
Youki is a container runtime written in Rust. Prior to version 0.5.5, if /proc and /sys in the rootfs are symbolic links, they can potentially be exploited to gain access to the host root filesystem. This issue has been patched in version 0.5.5.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- High
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Youki Symlink Following Vulnerability
Youki is a container runtime written in Rust. Prior to version 0.5.5, if /proc and /sys in the rootfs are symbolic links, they can potentially be exploited to gain access to the host root filesystem. This issue has been patched in version 0.5.5.
- Record
CVE-2025-54867- CVSS 3.1
- 7.0 High
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-61
- Updated
- 2026-11-02
EUVDEUVD-2025-24859
Youki is a container runtime written in Rust. Prior to version 0.5.5, if /proc and /sys in the rootfs are symbolic links, they can potentially be exploited to gain access to the host root filesystem. This issue has been patched in version 0.5.5.
- Record
EUVD-2025-24859- CVSS 3.1
- 7.0 High
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-j26p-6wx7-f3pw
Youki: If /proc and /sys in the rootfs are symbolic links, they can potentially be exploited to gain access to the host root filesystem.
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:
- Record
GHSA-j26p-6wx7-f3pw- CVSS 3.1
- 7.0 High
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-61
- Updated
- 2026-11-02
NVD
Youki is a container runtime written in Rust. Prior to version 0.5.5, if /proc and /sys in the rootfs are symbolic links, they can potentially be exploited to gain access to the host root filesystem. This issue has been patched in version 0.5.5.
- Record
CVE-2025-54867- CVSS 3.1
- 7.0 High
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-61
- Updated
- 2026-11-02
OSV
Youki Symlink Following Vulnerability
Youki is a container runtime written in Rust. Prior to version 0.5.5, if /proc and /sys in the rootfs are symbolic links, they can potentially be exploited to gain access to the host root filesystem. This issue has been patched in version 0.5.5.
- Record
CVE-2025-54867- CVSS 3.1
- 7.0 High
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-61
- Updated
- 2026-11-02
OSVGHSA-j26p-6wx7-f3pw
Youki: If /proc and /sys in the rootfs are symbolic links, they can potentially be exploited to gain access to the host root filesystem.
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:
- Record
GHSA-j26p-6wx7-f3pw- CVSS 3.1
- 7.0 High
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-61
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
youkicrates.io |
before 0.5.5 | 0.5.5 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2025-54867 is a high vulnerability (CVSS 7.0) in Youki-dev Youki, published August 14, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.19%, the 9th percentile. Fixed in youki 0.5.5.
References
github.com/youki-dev/youki/security/advisories/GHSA-j26p-6wx7-f3pw
nvd.nist.gov/vuln/detail/CVE-2025-54867