CVE-2025-31133

runc is a CLI tool for spawning and running containers according to the OCI specification. In 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 files, runc would not perform sufficient verification that the source of the bind-mount (i.e., the container's /dev/null) was actually a real /dev/null inode when using the container's /dev/null to mask. This exposes two methods of attack: an arbitrary mount gadget, leading to host information disclosure, host denial of service, container escape, or a bypassing of maskedPaths. This issue is fixed in versions 1.2.8, 1.3.3 and 1.4.0-rc.3.

Affected products

Alt Linux, Almalinux, Centos, Debian, Linuxmint, Red Hat, Red Os, Rocky Linux

Linuxfoundation Runc

< 1.2.8, 1.3.3, 1.4.0

Fix

Available

CVSS 3.1

7.8 HIGH

EPSS

0.8% (56th percentile)

Weakness

CWE-61, CWE-363

NVD status

Analyzed

Published

2025-11-06