CVE-2026-59167

SunEditor is a lightweight and powerful WYSIWYG editor in vanilla JavaScript with no dependencies. Prior to 2.47.11, the sanitizer in src/lib/core.js does not consistently reject namespaced or custom HTML elements, allowing event-handler attributes to remain on crafted elements. When an application renders attacker-controlled editor content and a user interacts with the element, the retained handler can execute script in the application's browser origin, enabling stored cross-site scripting, data exposure, or unauthorized browser-context actions. This issue is fixed in version 2.47.11.

  • Published Sep 23, 2026
  • CVSS 10.0 critical
  • 0.4% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

CVE-2026-59167 at the National Vulnerability Database