CVE-2026-65898

High

Description

DOMPurify before 3.4.11 fails to clone the ALLOWED_ATTR allowlist when setConfig() is used with an uponSanitizeAttribute hook, allowing the hook to permanently mutate the shared allowlist. Attackers can register a hook that conditionally allows dangerous attributes like onerror for trusted elements, then submit untrusted content that inherits the polluted allowlist and executes event handlers as stored XSS.

SeverityHigh

CVSS7.2

Exploit probability—

ProductCure53 Dompurify

PublishedJul 23, 2026

First seenJul 23, 2026

Weakness typeCWE-79Cross-site scripting (XSS)

How to fix

Update

cure53 dompurify3.4.11 or later
dompurify3.4.11 or later

Vendor advisories

github.com/cure53/DOMPurify/security/advisories/GHSA-cmwh-pvxp-8882

Affected products

Product	Affected versions	Fixed in
cure53 dompurify	v < 3.4.11	3.4.11
dompurifynpm	v < 3.4.11	3.4.11

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.