{"id":"CVE-2026-118661","published":"2026-10-28T21:16:56.267","lastModified":"2026-10-28T21:16:56.267","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.","cvssScore":6.5,"cvssSeverity":"MEDIUM","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","cwes":["CWE-565"],"vendors":[],"products":[],"references":[{"url":"https://github.com/capricorn86/happy-dom/commit/f21dbd7d0a0c63cdd41954ba5d0f05def4e0f2b3","tags":[]},{"url":"https://github.com/capricorn86/happy-dom/pull/2477","tags":[]},{"url":"https://github.com/capricorn86/happy-dom/releases/tag/v20.14.6","tags":[]},{"url":"https://github.com/capricorn86/happy-dom/security/advisories/GHSA-5fpq-26gf-qwcr","tags":[]}],"exploitRefs":[{"url":"https://github.com/capricorn86/happy-dom/commit/f21dbd7d0a0c63cdd41954ba5d0f05def4e0f2b3","tags":[]},{"url":"https://github.com/capricorn86/happy-dom/pull/2477","tags":[]},{"url":"https://github.com/capricorn86/happy-dom/releases/tag/v20.14.6","tags":[]},{"url":"https://github.com/capricorn86/happy-dom/security/advisories/GHSA-5fpq-26gf-qwcr","tags":[]}],"hasPoc":true,"ai":null}