CVE-2025-31133
runc container escape via "masked path" abuse due to mount race conditions
HIGH 7.3EPSS 0.8%
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
- opencontainers · runc
- CVSS v4.0 GITHUB
- 7.3 HIGH
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS v4.0 GitHub
- 7.3 HIGH
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H - CVSS v3.1 NVD
- 7.8 HIGH
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H - EPSS
- 0.84% chance of exploitation in the next 30 days, 57th percentile
- Published
- 2025-11-06
Proof-of-concept exploits (3)
- C-h4ck-0/Learn-about-cve-2025-31133-poc2★ · 2026-04-02
- raesene/vuln_pocs5★ · 2026-09-24
- skynet-f-nvidia/CVE-2025-311332★ · 2025-11-12
Security advisories
- opencontainers/runc/security/advisories/GHSA-9493-h29p-rfm2
- advisories/GHSA-9493-h29p-rfm2
- opencontainers/runc/commit/1a30a8f3d921acbbb6a4bb7e99da2c05f8d48522