{"id":"CVE-2026-41579","state":"PUBLISHED","title":"runc: Malicious image with /dev symlink can trigger limited host filesystem integrity violations","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.","publishedAt":"2026-07-01T00:02:08.639Z","updatedAt":"2026-07-01T13:35:41.354Z","severity":{"score":3.3,"label":"Low","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["opencontainers runc"],"affected":[{"vendor":"opencontainers","product":"runc","versions":[{"version":"< 1.3.6","status":"affected"},{"version":">= 1.4.0-rc.1, < 1.4.3","status":"affected"},{"version":">= 1.5.0-rc.1, < 1.5.0-rc.3","status":"affected"}]}],"references":["https://github.com/opencontainers/runc/security/advisories/GHSA-xjvp-4fhw-gc47","https://github.com/opencontainers/runc/commit/864db8042dbb"],"weaknesses":["CWE-61"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/41xxx/CVE-2026-41579.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-41579","state":"PUBLISHED","datePublished":"2026-07-01T00:02:08.639Z","dateUpdated":"2026-07-01T13:35:41.354Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-04-21T14:15:21.958Z"},"containers":{"cna":{"title":"runc: Malicious image with /dev symlink can trigger limited host filesystem integrity violations","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"opencontainers","product":"runc","versions":[{"version":"< 1.3.6","status":"affected"},{"version":">= 1.4.0-rc.1, < 1.4.3","status":"affected"},{"version":">= 1.5.0-rc.1, < 1.5.0-rc.3","status":"affected"}]}],"references":[{"url":"https://github.com/opencontainers/runc/security/advisories/GHSA-xjvp-4fhw-gc47","name":"https://github.com/opencontainers/runc/security/advisories/GHSA-xjvp-4fhw-gc47","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/opencontainers/runc/commit/864db8042dbb","name":"https://github.com/opencontainers/runc/commit/864db8042dbb","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"LOCAL","availabilityImpact":"NONE","baseScore":3.3,"baseSeverity":"LOW","confidentialityImpact":"NONE","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-61","lang":"en","description":"CWE-61: UNIX Symbolic Link (Symlink) Following","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-07-01T00:02:08.639Z"},"source":{"advisory":"GHSA-xjvp-4fhw-gc47","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-01T13:34:05.348945Z","id":"CVE-2026-41579","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-07-01T13:35:41.354Z"}}]}}}