CVE-2026-65904
Severity CVSS v4.0:
LOW
Type:
Unavailable / Other
Publication date:
23/07/2026
Last modified:
23/07/2026
Description
DOMPurify through 3.3.3 fails to sanitize DOM elements passed via IN_PLACE mode when the element originates from a different window/realm (e.g., an iframe's contentDocument). A cross-realm instanceof check in the private _isNode() function returns false for foreign-realm nodes, causing DOMPurify to stringify the element (yielding '[object HTMLDivElement]'), silently reset IN_PLACE to false, and return the unsanitized element unchanged with any XSS payloads intact. The vendor considers this an edge case outside DOMPurify's threat model and, at time of publication, no fix was planned.
Impact
Base Score 4.0
2.30
Severity 4.0
LOW
Base Score 3.x
4.70
Severity 3.x
MEDIUM



