Description
DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Prior to 3.4.6, DOMPurify.sanitize(node, { IN_PLACE: true }) accepted same-origin foreign-realm DOM nodes while follow-on checks used parent-realm constructors, causing instanceof checks for forms, named node maps, document fragments, and elements to fail and skip clobber, template-content, and shadow-DOM sanitization branches so executable markup could survive. This issue is fixed in version 3.4.6.
Affected products
cure53: dompurify
References4
- github.com/cure53/DOMPurify/security/advisories/GHSA-hpcv-96wg-… ExploitMitigationVendor Advisory
- github.com/cure53/DOMPurify/security/advisories/GHSA-hpcv-96wg-… ExploitMitigationVendor Advisory
- github.com/cure53/DOMPurify/commit/bb7739e5bccec7e1ab3dae3f3e42… Patch
- github.com/cure53/DOMPurify/releases/tag/3.4.6 Release Notes
Metrics
- CVSS 3.1
-
6.1
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 35 · as of 15 November 2026
- CWE
- CWE-79CWE-501CWE-693
Could this be exploited in your environment?
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