CVE-2026-41579
runc is a CLI tool for spawning and running containers according to the OCI specification. In versions prior to 1.3.6, 1.4.0-rc.1, 1.4.0-rc.12, 1.5.0-rc.1, and 1.5.0-rc.1, when setting up the container rootfs, setupPtmx and setupDevSymlinks call os.Remove and os.Symlink with a filepath.Join string which allow an image with /dev as a symlink to trick runc into deleting files called ptmx on the host or creating a hardcoded set of symlinks with specific names and targets in an arbitrary pre-existing host directory. This issue is not exploitable under Docker, because Docker creates a top-level read-only layer that masks any malicious /dev symlink present in the container image — unlike some other Linux container tooling, whose higher-level runtimes built on runc remain exposed to exploitation via a malicious image. This issue has been fixed in versions 1.3.6, 1.4.3 and 1.5.0.
- CVSS 3.1
- 3.3
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N - EPSS
- 0.2% chance of exploitation in the next 30 days; higher than 8% of CVEs (scores of 2026-10-25)
- CWE
- CWE-61
- Published
- Modified
- Record from
- the NVD, synced
Affected
- linuxfoundation:runc
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-xjvp-4fhw-gc47 | Go | github.com/opencontainers/runc | <1.3.6 | 1.3.6 |
| GHSA-xjvp-4fhw-gc47 | Go | github.com/opencontainers/runc | >=1.4.0 <1.4.3 | 1.4.3 |
| GHSA-xjvp-4fhw-gc47 | Go | github.com/opencontainers/runc | >=1.5.0-rc.1 <1.5.0-rc.3 | 1.5.0-rc.3 |
| GO-2026-5761 | Go | github.com/opencontainers/runc | <1.3.6 >=1.4.0 <1.4.3 >=1.5.0-rc.1 <1.5.0-rc.3 | 1.3.6, 1.4.3, 1.5.0-rc.3 |