{"id":"CVE-2026-118660","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-118660","summary":"Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. Prior to 21.0.0, Happy DOM loads iframe src URLs and link rel=\"stylesheet\" href URLs…","details":"Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. Prior to 21.0.0, Happy DOM loads iframe src URLs and link rel=\"stylesheet\" href URLs by default while parsing untrusted HTML on the server because disableIframePageLoading and disableCSSFileLoading default to false. An attacker who controls parsed HTML can therefore cause server-side requests to arbitrary internal or cloud endpoints without an application opt-in and may expose confidential responses or credentials returned by those endpoints. This issue is fixed in version 21.0.0.","published":"2026-10-28T21:16:56.123","modified":"2026-10-28T21:16:56.123","cvss":{"score":8.6,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[],"fix":{"url":"https://github.com/capricorn86/happy-dom/commit/0a99c7525a1d0043e3182843ae33466ab7b19e74","label":"capricorn86/happy-dom@0a99c75"},"references":[{"type":"WEB","url":"https://github.com/capricorn86/happy-dom/commit/0a99c7525a1d0043e3182843ae33466ab7b19e74"},{"type":"WEB","url":"https://github.com/capricorn86/happy-dom/pull/2502"},{"type":"WEB","url":"https://github.com/capricorn86/happy-dom/releases/tag/v21.0.0"},{"type":"WEB","url":"https://github.com/capricorn86/happy-dom/security/advisories/GHSA-c8p4-j97h-3vg8"}],"provenance":{"sources":["OSV.dev","NVD","FIRST.org (EPSS)"],"lastVerified":"2026-10-28T21:16:56.123"}}