Linuxfoundation: community verdicts

runc is a CLI tool for spawning and running containers on Linux according to the OCI specification. In runc 1.1.11 and earlier, due to an internal file descriptor leak, an attacker could cause a newly-spawned container process (from runc exec) to have a working directory in the host filesystem namespace, allowing for a container escape by giving access to the host filesystem ("attack 2"). The same attack could be used by a malicious image to allow a container process to gain access to the host filesystem through runc run ("attack 1"). Variants of attacks 1 and 2 could be also be used to overwrite semi-arbitrary host binaries, allowing for complete container escapes ("attack 3a" and "attack 3b"). runc 1.1.12 includes patches for this issue.

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.