{"schemaVersion":3,"id":"CVE-2026-6414","aliases":["GHSA-x428-ghpx-8j92"],"status":"published","duplicateOf":null,"title":null,"description":"@fastify/static versions 8.0.0 through 9.1.0 decode percent-encoded path separators (%2F) before filesystem resolution, while Fastify's router treats them as literal characters. This mismatch allows attackers to bypass route-based middleware or guards that protect files served by @fastify/static. For example, a route guard on a protected path can be circumvented by encoding the path separator in the URL. Upgrade to @fastify/static 9.1.1 to fix this issue. 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