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.
Metrics
CVSS 3.1 7.2/10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:NWeakness enumeration
Affected software
No affected versions have been published.
Timeline
- Published
- Jul 23, 2026
- Last modified
- Oct 24, 2026
- NVD status
- Analyzed