{"cve":"CVE-2025-25200","nvd":{"published":"2025-02-12T18:15:28.110","modified":"2026-06-17T09:00:28.320","status":"Analyzed","description":"Koa is expressive middleware for Node.js using ES2017 async functions. Prior to versions 0.21.2, 1.7.1, 2.15.4, and 3.0.0-alpha.3, Koa uses an evil regex to parse the `X-Forwarded-Proto` and `X-Forwarded-Host` HTTP headers. This can be exploited to carry out a Denial-of-Service attack. Versions 0.21.2, 1.7.1, 2.15.4, and 3.0.0-alpha.3 fix the issue.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H","score":9.2},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-1333"],"references":["https://github.com/koajs/koa/blob/master/lib/request.js#L259","https://github.com/koajs/koa/blob/master/lib/request.js#L404","https://github.com/koajs/koa/commit/5054af6e31ffd451a4151a1fe144cef6e5d0d83c","https://github.com/koajs/koa/commit/5f294bb1c7c8d9c61904378d250439a321bffd32","https://github.com/koajs/koa/commit/93fe903fc966635a991bcf890cfc3427d33a1a08"],"products":["koajs:koa"],"source":"nvd","synced_at":"2026-10-19T21:59:18.731010617+00:00"},"epss":{"cve":"CVE-2025-25200","score":0.00841,"percentile":0.57904,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-593f-38f6-jp5m","url":"https://osv.dev/vulnerability/GHSA-593f-38f6-jp5m","summary":"Inefficient Regular Expression Complexity in koa","modified":"2025-02-12T19:27:07.225487Z","packages":[{"ecosystem":"npm","name":"koa","purl":"pkg:npm/koa","ranges":[">=2.0.0 <2.15.4"],"fixed":["2.15.4"]},{"ecosystem":"npm","name":"koa","purl":"pkg:npm/koa","ranges":[">=3.0.0-alpha.0 <3.0.0-alpha.3"],"fixed":["3.0.0-alpha.3"]},{"ecosystem":"npm","name":"koa","purl":"pkg:npm/koa","ranges":[">=1.0.0 <1.7.1"],"fixed":["1.7.1"]},{"ecosystem":"npm","name":"koa","purl":"pkg:npm/koa","ranges":["<0.21.2"],"fixed":["0.21.2"]}]}],"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."]}