{"id":"CVE-2026-25121","aliases":["GHSA-5g94-c2wx-8pxw","GO-2026-4405"],"url":"https://o3.security/vulnerability/CVE-2026-25121","summary":"apko is vulnerable to path traversal in apko dirFS which allows filesystem writes outside base","details":"apko allows users to build and publish OCI container images built from apk packages. From version 0.14.8 to before 1.1.1, a path traversal vulnerability was discovered in apko's dirFS filesystem abstraction. An attacker who can supply a malicious APK package (e.g., via a compromised or typosquatted repository) could create directories or symlinks outside the intended installation root. The MkdirAll, Mkdir, and Symlink methods in pkg/apk/fs/rwosfs.go use filepath.Join() without validating that the resulting path stays within the base directory. This issue has been patched in version 1.1.1.","published":"2026-02-04T19:02:17.979Z","modified":"2026-08-07T11:50:38.371969834Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"chainguard.dev/apko","fixedVersion":"1.1.0"}],"fix":{"url":"https://github.com/chainguard-dev/apko/commit/d8b7887a968a527791b3c591ae83928cb49a9f14","label":"chainguard-dev/apko@d8b7887"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25121.json"},{"type":"ADVISORY","url":"https://github.com/chainguard-dev/apko/security/advisories/GHSA-5g94-c2wx-8pxw"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-25121"},{"type":"FIX","url":"https://github.com/chainguard-dev/apko/commit/d8b7887a968a527791b3c591ae83928cb49a9f14"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T11:50:38.371969834Z"}}