{"id":"CVE-2021-22964","aliases":["GHSA-pgh6-m65r-2rhq"],"url":"https://o3.security/vulnerability/CVE-2021-22964","summary":"DOS and Open Redirect with user input","details":"A redirect vulnerability in the `fastify-static` module version >= 4.2.4 and < 4.4.1 allows remote attackers to redirect Mozilla Firefox users to arbitrary websites via a double slash `//` followed by a domain: `http://localhost:3000//a//youtube.com/%2e%2e%2f%2e%2e`.A DOS vulnerability is possible if the URL contains invalid characters `curl --path-as-is \"http://localhost:3000//^/..\"`The issue shows up on all the `fastify-static` applications that set `redirect: true` option. By default, it is `false`.","published":"2021-10-14T15:15:08.933Z","modified":"2026-07-09T00:06:05.686755Z","cvss":{"score":8.8,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":1,"affectedPackages":[{"ecosystem":"npm","name":"fastify-static","fixedVersion":"4.4.1"}],"fix":null,"references":[{"type":"FIX","url":"https://hackerone.com/reports/1361804"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-09T00:06:05.686755Z"}}