CVE-2026-41238

Published Apr 23, 2026

Last updated 4 hours ago

Overview

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.
Source
security-advisories@github.com
NVD status
Deferred

Risk scores

CVSS 3.1

Type
Secondary
Base score
6.9
Impact score
4.7
Exploitability score
1.6
Vector string
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:N
Severity
MEDIUM

Weaknesses

security-advisories@github.com
CWE-79

Social media

Hype score
Not currently trending