{"id":"CVE-2025-62161","aliases":["GHSA-4g74-7cff-xcv8"],"url":"https://o3.security/vulnerability/CVE-2025-62161","summary":"youki container escape via \"masked path\" abuse due to mount race conditions","details":"### Impact ###\n\nyouki utilizes bind mounting the container's `/dev/null` as a file mask. When performing this operation, the initial validation of the source `/dev/null` was insufficient. Specifically, we initially failed to verify whether `/dev/null` was genuinely present. However, we did perform validation to ensure that the `/dev/null` path existed within the container, including checking for symbolic links. Additionally, there was a vulnerability in the timing between validation and the actual mount operation.\n\nAs a result, by replacing `/dev/null` with a symbolic link, we can bind-mount arbitrary files from the host system.\n\nThis is a different project, but the core logic is similar to the CVE in runc. Issues were identified in runc, and verification was also conducted in youki to confirm the problems.\nhttps://github.com/opencontainers/runc/security/advisories/GHSA-9493-h29p-rfm2\n\n### Credits\n\nThanks to Lei Wang (@ssst0n3 from Huawei) for finding and reporting the original runc's vulnerability (Attack 1), and Li Fubang (@lifubang from acmcoder.com, CIIC) for discovering another attack vector in runc (Attack 2) based on @ssst0n3's initial findings.\n\nAlso, @cyphar helped youki in finding the problem.","published":"2025-11-05T23:09:09.014Z","modified":"2026-08-12T03:51:48.464242562Z","cvss":null,"epss":{"score":0.00242,"percentile":0.1509,"asOf":"2026-08-24"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"crates.io","name":"youki","fixedVersion":"0.5.7"}],"fix":{"url":"https://github.com/youki-dev/youki/commit/5886c91073b9be748bd8d5aed49c4a820548030a","label":"youki-dev/youki@5886c91"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/62xxx/CVE-2025-62161.json"},{"type":"ADVISORY","url":"https://github.com/youki-dev/youki/security/advisories/GHSA-4g74-7cff-xcv8"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-62161"},{"type":"FIX","url":"https://github.com/youki-dev/youki/commit/5886c91073b9be748bd8d5aed49c4a820548030a"},{"type":"WEB","url":"https://github.com/opencontainers/runc/security/advisories/GHSA-9493-h29p-rfm2"},{"type":"PACKAGE","url":"https://github.com/youki-dev/youki"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:48.464242562Z"}}