CVE-2026-49459 DOMPurify: IN_PLACE mode preserves attributes of a clobbered root element, allowing XSS via attacker-controlled root DOM

DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Prior to 3.4.6, DOMPurify.sanitizeroot, INPLACE: true could preserve event-handler attributes on an attacker-controlled root when a descendant name clobbered properties checked by isClobbered, because forceRemove...

CVE-2026-49459 DOMPurify: IN_PLACE mode preserves attributes of a clobbered root element, allowing XSS via attacker-controlled root DOM

DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Prior to 3.4.6, DOMPurify.sanitizeroot, INPLACE: true could preserve event-handler attributes on an attacker-controlled root when a descendant name clobbered properties checked by isClobbered, because forceRemove...

CVE-2026-49459

CVE-2026-49459 affects DOMPurify prior to 3.4.6, where IN_PLACE mode could retain event-handler attributes on an attacker‑controlled root DOM due to _isClobbered logic and incomplete removal paths. Affected component: DOMPurify.sanitize(root, { IN_PLACE: true }) with a clobbered root form. Conseq...