CVE-2026-49978 — DOMPurify IN_PLACE Sanitization Bypass via Attached Shadow Root Inside <template>.content
DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Prior to 3.4.7, DOMPurify IN_PLACE sanitization could skip shadow contents attached to an eleme…
Published: 2026-07-14 · CVSS: 6.3 · CVSS 4.0
DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Prior to 3.4.7, DOMPurify IN_PLACE sanitization could skip shadow contents attached to an element inside <template>.content, allowing attacker-controlled markup such as event handlers, JavaScript URLs, or scripts to survive and execute when an application cloned and inserted the sanitized template. This issue is fixed in version 3.4.7.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7