{"cve":"CVE-2021-22963","nvd":{"published":"2021-10-14T15:15:08.877","modified":"2026-06-17T03:38:07.070","status":"Modified","description":"A redirect vulnerability in the fastify-static module version < 4.2.4 allows remote attackers to redirect users to arbitrary websites via a double slash // followed by a domain: http://localhost:3000//google.com/%2e%2e.The issue shows up on all the fastify-static applications that set redirect: true option. By default, it is false.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","score":6.1},"cwes":["CWE-601"],"references":["https://hackerone.com/reports/1354255","https://hackerone.com/reports/1354255"],"products":["fastify:fastify-static"],"source":"nvd","synced_at":"2026-10-19T21:24:39.218183596+00:00"},"epss":{"cve":"CVE-2021-22963","score":0.01169,"percentile":0.67407,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-p6vg-p826-qp3v","url":"https://osv.dev/vulnerability/GHSA-p6vg-p826-qp3v","summary":"URL Redirection to Untrusted Site ('Open Redirect') in fastify-static","modified":"2023-11-08T04:05:02.185397Z","packages":[{"ecosystem":"npm","name":"fastify-static","purl":"pkg:npm/fastify-static","ranges":["<4.2.4"],"fixed":["4.2.4"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}