CVE-2026-41579

LOW

runc: Malicious image with /dev symlink can trigger limited host filesystem integrity violations

Title source: cna
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2026-41579. PoCs published by HermesNA-1.

AI-analyzed exploit summary This repository contains an auto-generated stub module for CVE-2026-41579, a vulnerability in runc (CLI tool for OCI containers). The code includes metadata and a placeholder structure but lacks actual exploit implementation, referencing only advisory links and a patch commit.

Description

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 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.

Exploits (1)

github STUB 1 stars
by HermesNA-1 · pythonpoc
https://github.com/HermesNA-1/SnakeSploit/tree/main/data/modules_generated/cve-2026-41579_runc_cli.py

This repository contains an auto-generated stub module for CVE-2026-41579, a vulnerability in runc (CLI tool for OCI containers). The code includes metadata and a placeholder structure but lacks actual exploit implementation, referencing only advisory links and a patch commit.

Classification
Stub 99%
Attack Type
Other
Complexity
Moderate
Reliability
Theoretical
Target: runc 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
No auth needed
Prerequisites: Network access to the target system running vulnerable runc versions · Knowledge of the specific vulnerability mechanics (not provided in the stub)
mistral-large-3 · analyzed Jul 09, 2026 Full analysis →

References (2)

Core 2

Scores

CVSS v3 3.3
EPSS 0.0022
EPSS Percentile 12.7%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-61
Status published
Products (5)
linuxfoundation/runc 1.5.0 rc1 (2 CPE variants)
linuxfoundation/runc < 1.3.6
opencontainers/runc < 1.3.6
opencontainers/runc >= 1.4.0-rc.1, < 1.4.3
opencontainers/runc >= 1.5.0-rc.1, < 1.5.0-rc.3
Published Jul 01, 2026
Tracked Since Jul 01, 2026