CVE-2025-52881
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk45th percentile - higher than 45% of all known CVEs
Summary
In runc 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. This redirect could be through symbolic links in a tmpfs or other methods such as regular bind-mounts. This issue is fixed in versions 1.2.8, 1.3.3, and 1.4.0-rc.3.
Risk Assessment
An attacker can affect procfs files, potentially leading to privilege escalation or container isolation breach, compromising host security.
Recommendation
Upgrade runc to version 1.2.8, 1.3.3, or 1.4.0-rc.3. Avoid using shared mounts in containers unless necessary.
Other vulnerabilities in runc
See all- CVE-2025-52565High
runc is a CLI tool for spawning and running containers according to the OCI specification. Versions 1.0.0-rc3 through 1.2.7, 1.3.0-rc.1 through 1.3.2, and 1.4.0-rc.1 through 1.4.0-rc.2, due to insufficient checks when bind-mounting `/dev/pts/$n` to `/dev/console` inside the container, an attacker can...
- CVE-2024-45310Medium
runc 1.1.13 and earlier, as well as 1.2.0-rc2 and earlier, can be tricked into creating empty files or directories in arbitrary locations in the host filesystem by sharing a volume between two containers and exploiting certain operations.
- CVE-2024-21626High
A vulnerability in runc 1.1.11 and earlier is caused by an internal file descriptor leak, allowing an attacker to set the working directory of a container process to the host filesystem namespace. This enables container escape and access to the host filesystem via runc exec or runc run. Additional attack variants allow overwriting host binaries, leading to complete container escape.
- CVE-2026-41579Low
In runc prior to versions 1.3.6, 1.4.3, and 1.5.0, setupPtmx and setupDevSymlinks use filepath.Join with os.Remove and os.Symlink, allowing an image with /dev as a symlink to delete the ptmx file on the host or create symlinks in an arbitrary host directory. This is not exploitable under Docker, but other container tooling built on runc remains exposed.
- CVE-2025-31133High
In runc versions 1.2.7 and below, 1.3.0-rc.1 through 1.3.1, 1.4.0-rc.1 and 1.4.0-rc.2, insufficient verification of the bind-mount source (e.g., container's /dev/null) allows attacks: arbitrary mount gadget leading to host information disclosure, host DoS, container escape, or bypassing maskedPaths.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS