CVE-2026-66010
DOMPurify before 3.4.12 fails to execute afterSanitizeElements hook for custom elements allowed via CUSTOM_ELEMENT_HANDLING.tagNameCheck, allowing attributes to bypass application security policies. Attackers can preserve sensitive attributes on custom elements that later re-inject them into innerHTML sinks, creating second-order XSS gadgets.
- Published Jul 24, 2026
- CVSS 5.1 medium
- 0.3% chance of exploitation in the next 30 days (EPSS)
- Public exploit code is available
- A fix is available
Affected software
In the news
- Multiple vulnerabilities in IBM products CERT-FR ·
- Multiple vulnerabilities in IBM products CERT-FR ·