CVE-2026-49458
MEDIUMDOMPurify: Cross-realm IN_PLACE sanitization leaves executable markup intact via realm-bound `instanceof` checks
Title source: cnaDescription
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.
References (3)
Core 3
Core References
X_Refsource_Confirm x_refsource_confirm
https://github.com/cure53/DOMPurify/security/advisories/GHSA-hpcv-96wg-7vj8
X_Refsource_Misc x_refsource_misc
https://github.com/cure53/DOMPurify/commit/bb7739e5bccec7e1ab3dae3f3e42d02db3acaaae
X_Refsource_Misc x_refsource_misc
https://github.com/cure53/DOMPurify/releases/tag/3.4.6
Scores
CVSS v3
6.1
EPSS
0.0038
EPSS Percentile
31.1%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
no
Technical Impact
partial
Details
CWE
CWE-501
CWE-693
CWE-79
Status
published
Products (2)
cure53/dompurify
< 3.4.6
cure53/DOMPurify
< 3.4.6
Published
Jul 14, 2026
Tracked Since
Jul 15, 2026