CVE-2026-41579
Linuxfoundation Runc ≤ 1.3.6
Raw vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:NSummary
CVE-2026-41579 is a low-severity UNIX Symbolic Link (Symlink) Following (CWE-61) vulnerability in Linuxfoundation Runc. Its CVSS base score is 3.3 (Low).
Operationally, exploitation aligns with the MITRE ATT&CK technique Escape to Host (T1611); ranked at the 9th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) and AC-6 (Least Privilege) — see the control section below for these in your framework.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-40859
Vulnerability Data
runc is a CLI tool for spawning and running containers according to the OCI specification. In versions prior to 1.3.6, 1.4.0-rc.1, 1.4.0-rc.12, 1.5.0-rc.1, and 1.5.0-rc.1, when setting up the container rootfs, setupPtmx and setupDevSymlinks call os.Remove and os.Symlink with a…
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filepath.Join string which allow an image with /dev as a symlink to trick runc into deleting files called ptmx on the host or creating a hardcoded set of symlinks with specific names and targets in an arbitrary pre-existing host directory. This issue is not exploitable under Docker, because Docker creates a top-level read-only layer that masks any malicious /dev symlink present in the container image — unlike some other Linux container tooling, whose higher-level runtimes built on runc remain exposed to exploitation via a malicious image. This issue has been fixed in versions 1.3.6, 1.4.3 and 1.5.0.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Vulnerability in runc enables symlink-based host filesystem manipulation from malicious container images, directly facilitating container escape to underlying host.
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
Mitigating Controls (NIST 800-53 r5) AI
Directly validates untrusted file paths and symlinks supplied by container images before os.Remove/os.Symlink operations are performed.
Limits the privileges of the runc process and container runtime so that symlink-induced deletions or link creations on the host are constrained.
Requires integrity verification of container images to detect malicious /dev symlinks before they are processed by runc.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure SDLC practices directly prevent introduction of symlink-following flaws in file-handling code.
Vulnerability identification can discover existing symlink issues but does not prevent or remediate them in code.
Least-privilege access policies can limit damage from symlink attacks but do not address the coding flaw itself.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing can detect symlink-following vulnerabilities before deployment, covering most of the weakness.
Secure-architecture principles require safe file-handling and canonicalization, directly addressing symlink attacks.
Secure-coding standards mandate explicit symlink checks and safe open patterns, fully mitigating CWE-61.
Access-control rules can restrict which files a process may open, reducing symlink-following risk but not eliminating the underlying path-resolution flaw.
Configuration management can enforce safe file-permission baselines that limit symlink abuse, but does not address the code flaw itself.