CVEvulnerability

CVE-2026-41238

6.9 MEDIUM Published 2026-04-23 Modified 2026-10-26 Official page ↗
Status
Deferred
Published
2026-04-23
Last modified
2026-10-26
Assigner
[email protected]
CVSS 3.1 ([email protected])
6.9 MEDIUM — CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:N
Weaknesses
CWE-1321, CWE-79

Description

DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Versions 3.0.1 through 3.3.3 are vulnerable to a prototype pollution-based XSS bypass. When an application uses `DOMPurify.sanitize()` with the default configuration (no `CUSTOM_ELEMENT_HANDLING` option), a prior prototype pollution gadget can inject permissive `tagNameCheck` and `attributeNameCheck` regex values into `Object.prototype`, causing DOMPurify to allow arbitrary custom elements with arbitrary attributes — including event handlers — through sanitization. Version 3.4.0 fixes the issue.

Related

Weakness · CWE (2)

  • CWE-1321 Improperly Controlled Modification of Object Prototype Attributes weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation weakness

References