Umbraco.Cms: XSS/HTML Injection in Umbraco Backoffice confirmation dialog
Date: 2026-05
Affected: nuget/Umbraco.Cms
Attack vector: xss
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2026-46609
CWE: CWE-79
CVSS: 4.6 (CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N)

### Impact Authenticated users are able to inject HTML vulnerability into an input field, which is rendered in the confirmation dialog without proper output encoding. ### Patches This issue has been patched in 17.4.0


Mitigations:

Architectural layers (MAESTRO):