CVE-2025-52881

CVE-2025-52881 is a high-severity vulnerability in Linuxfoundation Runc with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-61.

Key facts

Description

runc is a CLI tool for spawning and running containers according to the OCI specification. In versions 1.2.7, 1.3.2 and 1.4.0-rc.2, an attacker can trick runc into misdirecting writes to /proc to other procfs files through the use of a racing container with shared mounts (we have also verified this attack is possible to exploit using a standard Dockerfile with docker buildx build as that also permits triggering parallel execution of containers with custom shared mounts configured). This redirect could be through symbolic links in a tmpfs or theoretically other methods such as regular bind-mounts. While similar, the mitigation applied for the related CVE, CVE-2019-19921, was fairly limited and effectively only caused runc to verify that when LSM labels are written they are actually procfs files. This issue is fixed in versions 1.2.8, 1.3.3, and 1.4.0-rc.3.

Frequently asked questions

What is CVE-2025-52881?
runc is a CLI tool for spawning and running containers according to the OCI specification. In versions 1.2.7, 1.3.2 and 1.4.0-rc.2, an attacker can trick runc into misdirecting writes to /proc to other procfs files through the use of a racing container with shared mounts (we have also verified this attack is possible to exploit using a standard Dockerfile with docker buildx build as that also permits triggering parallel execution of containers with custom shared mounts configured). This redirect could be through symbolic links in a tmpfs or theoretically other methods such as regular bind-mounts. While similar, the mitigation applied for the related CVE, CVE-2019-19921, was fairly limited and effectively only caused runc to verify that when LSM labels are written they are actually procfs files. This issue is fixed in versions 1.2.8, 1.3.3, and 1.4.0-rc.3.
How severe is CVE-2025-52881?
CVE-2025-52881 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over local access with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-52881 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-52881?
CVE-2025-52881 primarily affects Linuxfoundation Runc. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-52881?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-52881 have an EU (EUVD) identifier?
Yes. CVE-2025-52881 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-37940.
When was CVE-2025-52881 published?
CVE-2025-52881 was published on 2025-11-06 and last updated on 2026-06-17.

References

Affected products (3)

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