{"cve":"CVE-2026-118661","nvd":{"published":"2026-10-28T21:16:56.267","modified":"2026-10-28T21:16:56.267","status":"Received","description":"Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. Prior to 20.14.6, Happy DOM's CookieContainer in src/cookie/CookieContainer.ts does not correctly validate or match Domain cookie attributes. It can accept a Domain unrelated to the origin setting the cookie, including a public suffix, and separately treats an unrelated suffix-sharing hostname as a match because cookieMatchesURL does not enforce a DNS-label boundary. In server-side rendering and prerendering applications that contact attacker-controlled origins and then make requests to a victim origin, these behaviors can plant and deliver a forged cookie, enabling cookie injection or session fixation. This issue is fixed in version 20.14.6.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","score":6.5},"cwes":["CWE-565"],"references":["https://github.com/capricorn86/happy-dom/commit/f21dbd7d0a0c63cdd41954ba5d0f05def4e0f2b3","https://github.com/capricorn86/happy-dom/pull/2477","https://github.com/capricorn86/happy-dom/releases/tag/v20.14.6","https://github.com/capricorn86/happy-dom/security/advisories/GHSA-5fpq-26gf-qwcr"],"products":[],"source":"nvd","synced_at":"2026-10-28T21:45:43.571453220+00:00"},"epss":null,"kev":null,"osv":[{"id":"GHSA-5fpq-26gf-qwcr","url":"https://osv.dev/vulnerability/GHSA-5fpq-26gf-qwcr","summary":"Happy DOM has cookie scope forgery: no DNS-label boundary on Domain= matching , attacker origin sets victim cookies","modified":"2026-10-28T21:15:05.095020046Z","packages":[{"ecosystem":"npm","name":"happy-dom","purl":"pkg:npm/happy-dom","ranges":["<20.14.6"],"fixed":["20.14.6"]}]}],"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."]}