{"cve":"CVE-2026-118659","nvd":{"published":"2026-10-28T21:16:55.967","modified":"2026-10-28T21:16:55.967","status":"Received","description":"Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. Prior to 21.0.2, the Happy DOM server-renderer package's ServerRendererServer accepts unauthenticated HTTP/2 requests and resolves attacker-controlled :path values against server.targetOrigin in #onIncomingRequest in packages/@happy-dom/server-renderer/src/ServerRendererServer.ts without confirming that the resolved origin remains trusted before calling fetch. A protocol-relative path can change the destination to an arbitrary HTTP or HTTPS endpoint reachable by the server, including local and internal services, and the proxy relays the fetched response headers and body to the requester. This issue is fixed in version 21.0.2.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","score":7.5},"cwes":["CWE-918"],"references":["https://github.com/capricorn86/happy-dom/commit/1f3ffdf634231361de1a2acb629b4fe8ee1bd85d","https://github.com/capricorn86/happy-dom/pull/2520","https://github.com/capricorn86/happy-dom/releases/tag/v21.0.2","https://github.com/capricorn86/happy-dom/security/advisories/GHSA-pmf4-3xr3-xjhg"],"products":[],"source":"nvd","synced_at":"2026-10-28T21:45:43.571453220+00:00"},"epss":null,"kev":null,"osv":[],"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."]}