CVE-2026-46680
This allows the Kubernetes runAsNonRoot restriction to be bypassed, causing unexpected behavior for environments that require containers to run as a non-root user.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.16%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
containerd is an open-source container runtime. In versions prior to 1.7.32, 2.0.9, 2.2.4 and 2.3.1, containers launched with a numeric User directive that cannot be parsed as a 32-bit integer are incorrectly treated as a username, leading to runAsNonRoot evasion. If a crafted image provides an /etc/passwd file mapping this large numeric string to root, the container ultimately runs as root (UID 0). This allows the Kubernetes runAsNonRoot restriction to be bypassed, causing unexpected behavior for environments that require containers to run as a non-root user. This issue has been fixed in versions 1.7.32, 2.0.9, 2.2.4 and 2.3.1.
- CVSS 4.0
- 7.3 HIGHCVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.16% probability · 6th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-269
- Affected
- linuxfoundation/containerd
- Source
- security-advisories@github.com
References
- https://github.com/containerd/containerd/security/advisories/GHSA-fqw6-gf59-qr4wMitigation, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.