CVE-2026-49458: CURE53 Dompurify

Medium severity, CVSS 6.1. EPSS: 0.4% chance of exploitation in the next 30 days.

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: before 3.4.6 (fixed in 3.4.6)

Published 2026-07-14. Last modified 2026-07-21.