{"id":"GHSA-x428-ghpx-8j92","summary":"@fastify/static vulnerable to route guard bypass via encoded path separators","details":"### Impact\n\n`@fastify/static` v9.1.0 and earlier decodes percent-encoded path separators (`%2F`) before filesystem resolution, but Fastify's router treats them as literal characters. This creates a routing mismatch: route guards on `/admin/*` do not match `/admin%2Fsecret.html`, but @fastify/static decodes it to `/admin/secret.html` and serves the file.\n\nApplications that rely on route-based middleware or guards to protect files served by @fastify/static can be bypassed with encoded path separators.\n\n### Patches\n\nUpgrade to `@fastify/static` \u003e= 9.1.1.\n\n### Workarounds\n\nNone. Upgrade to the patched version.","aliases":["CVE-2026-6414"],"modified":"2026-05-01T04:44:10.819394663Z","published":"2026-04-16T22:34:03Z","related":["CVE-2026-6414"],"database_specific":{"nvd_published_at":"2026-04-16T13:16:52Z","cwe_ids":["CWE-177"],"severity":"MODERATE","github_reviewed":true,"github_reviewed_at":"2026-04-16T22:34:03Z"},"references":[{"type":"WEB","url":"https://github.com/fastify/fastify-static/security/advisories/GHSA-x428-ghpx-8j92"},{"type":"WEB","url":"https://github.com/fastify/middie/security/advisories/GHSA-cxrg-g7r8-w69p"},{"type":"WEB","url":"https://github.com/honojs/hono/security/advisories/GHSA-q5qw-h33p-qvwr"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-6414"},{"type":"WEB","url":"https://cna.openjsf.org/security-advisories.html"},{"type":"PACKAGE","url":"https://github.com/fastify/fastify-static"}],"affected":[{"package":{"name":"@fastify/static","ecosystem":"npm","purl":"pkg:npm/%40fastify/static"},"ranges":[{"type":"SEMVER","events":[{"introduced":"8.0.0"},{"fixed":"9.1.1"}]}],"database_specific":{"last_known_affected_version_range":"\u003c= 9.1.0","source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/04/GHSA-x428-ghpx-8j92/GHSA-x428-ghpx-8j92.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N"}]}