CVE-2026-65904

MEDIUM

DOMPurify before 3.4.4 Cross-Site Scripting via IN_PLACE mode

Title source: cna
STIX 2.1

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.

References (2)

Core 2
Core References
Third Party Advisory third-party-advisory
VulnCheck Advisory: DOMPurify before 3.4.4 Cross-Site Scripting via IN_PLACE mode
https://www.vulncheck.com/advisories/dompurify-before-cross-site-scripting-via-in-place-mode
Vendor Advisory vendor-advisory
GitHub Security Advisory (GHSA-4w3q-35jp-p934)
https://github.com/cure53/DOMPurify/security/advisories/GHSA-4w3q-35jp-p934

Scores

CVSS v3 4.7
EPSS 0.0016
EPSS Percentile 6.1%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/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-754
Status published
Products (4)
cure53/DOMPurify < 3.3.3
cure53/DOMPurify < 3.4.4
cure53/dompurify < 3.4.4
cure53/DOMPurify 3.4.4
Published Jul 23, 2026
Tracked Since Jul 23, 2026