CVE-2024-21626
HighCVSS 8.6Exploitation Probability (EPSS)
Very high risk97th percentile - higher than 97% of all known CVEs
Summary
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.
Risk Assessment
The organization faces the risk of full host compromise, where an attacker can access sensitive data, modify system files, or execute malicious code outside the container.
Recommendation
Immediately update runc to version 1.1.12 or later. Before updating, restrict trusted container images and monitor container activity for suspicious behavior.
Original NVD description (English source)
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.