{"schemaVersion":3,"id":"CVE-2026-6270","aliases":["GHSA-72c6-fx6q-fr5w"],"status":"published","duplicateOf":null,"title":null,"description":"@fastify/middie versions 9.3.1 and earlier do not register inherited middleware directly on child plugin engine instances. When a Fastify application registers authentication middleware in a parent scope and then registers child plugins with @fastify/middie, the child scope does not inherit the parent middleware. This allows unauthenticated requests to reach routes defined in child plugin scopes, bypassing authentication and authorization checks. Upgrade to @fastify/middie 9.3.2 to fix this issue. 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