{"id":"CVE-2026-15074","aliases":["GHSA-83w8-p2f5-377r"],"url":"https://o3.security/vulnerability/CVE-2026-15074","summary":"@fastify/static vulnerable to route guard bypass via path traversal","details":"### Impact\n\n`@fastify/static` is vulnerable to a bypass of route-based middleware and guards via non-leading `..` and `%2E%2E` path segments. `find-my-way` does not normalize `..` when matching routes, so a request such as `/foo/../deep/secret.txt` matches the static plugin's catch-all instead of the guarded `/deep/*`. The `getPathnameForSend` helper introduced by the fix for [GHSA-x428-ghpx-8j92](https://github.com/fastify/fastify-static/security/advisories/GHSA-x428-ghpx-8j92) only guards against the `%2F` variant; `..` and `%2E%2E` survive the `decodeURI` + `encodeURI` round-trip and are then collapsed away by `@fastify/send`'s `path.normalize` before its own traversal guard runs.\n\nApplications that rely on route-based middleware or guards to protect files served by `@fastify/static` can be bypassed with non-leading dot-dot path segments.\n\n### Patches\n\nUpgrade to `@fastify/static` 10.1.1.\n\n### Workarounds\n\nDo not use route-based middlewares or guards to protect files served by `@fastify/static`.","published":"2026-07-23T03:01:47.887Z","modified":"2026-10-21T02:56:10.597586894Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"},"epss":{"score":0.00672,"percentile":0.5033,"asOf":"2026-09-16"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"@fastify/static","fixedVersion":"10.1.1"}],"fix":{"url":"https://github.com/fastify/fastify-static/commit/db4276f846ba56b21f93768cd6636ee5e2fc58b1","label":"fastify/fastify-static@db4276f"},"references":[{"type":"ADVISORY","url":"https://cna.openjsf.org/security-advisories.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/15xxx/CVE-2026-15074.json"},{"type":"ADVISORY","url":"https://github.com/fastify/fastify-static/security/advisories/GHSA-83w8-p2f5-377r"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-15074"},{"type":"WEB","url":"https://github.com/fastify/fastify-static/commit/db4276f846ba56b21f93768cd6636ee5e2fc58b1"},{"type":"PACKAGE","url":"https://github.com/fastify/fastify-static"},{"type":"WEB","url":"https://github.com/fastify/fastify-static/releases/tag/v10.1.1"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-21T02:56:10.597586894Z"}}