CVE-2026-65904: 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 cro

mediumCVSS 4.7CVE-2026-65904

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.

Details

Source: NVD Recent CVEs (US · database · site)
Severity: medium — CVSS 4.7
Published: 2026-07-23
Last updated: 2026-07-28
Exploitation: Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-65904

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-659040.17% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 6% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-65904	coverage & exploitation status	NVD · CVE.org

Recent advisories for DOMPurify

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

high[NEW] [high] Red Hat Ansible Automation Platform (node-tar, linkify-it, protobufjs, brace-expansion, fast-uri,…cert-bund · 2026-07-31
mediumCVE-2026-66010: DOMPurify before 3.4.12 fails to execute afterSanitizeElements hook for custom elements allowe…nvd · 2026-07-24
mediumCVE-2026-65914: DOMPurify before 3.3.2 contains a mutation-XSS vulnerability when sanitized HTML is reinserted…nvd · 2026-07-23
mediumCVE-2026-65913: DOMPurify before 3.3.2 contains a prototype pollution vulnerability in USE_PROFILES mode that …nvd · 2026-07-23
mediumCVE-2026-65912: DOMPurify before 3.3.2 contains a URI validation bypass vulnerability when ADD_ATTR is provide…nvd · 2026-07-23
mediumCVE-2026-65911: In DOMPurify through 3.3.3, function predicates supplied via ADD_ATTR or ADD_TAGS to DOMPurify…nvd · 2026-07-23

CVE-2026-65904: 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 cro

Details

Exploitation outlook

Referenced CVEs

Recent advisories for DOMPurify

More from NVD Recent CVEs