CVE-2026-41238
MEDIUM 6.9EPSS 0.2%
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.
- CVSS v3.1
- 6.9 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:N - CVSS v3.1
- 6.9 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:N - EPSS
- 0.22% chance of exploitation in the next 30 days, 13th percentile
- Published
- 2026-04-23
Proof-of-concept exploits (2)
- advisories/GHSA-v9jr-rg53-9pgp
- snowcapped-morula414/bingo3★ · 2026-08-29