Silverstripe Framework has a XSS vulnerability in HTML editor
Date: 2025-04
Affected: composer/silverstripe/framework
Attack vector: xss
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2025-30148
CWE: CWE-79
CVSS: 5.4 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N)

### Impact A bad actor with access to edit content in the CMS could send a specifically crafted encoded payload to the server, which could be used to inject a JavaScript payload on the front end of the site. The payload would be sanitised on the client-side, but server-side sanitisation doesn't catch it. The server-side sanitisation logic has been updated to sanitise against this attack. ### Reported by James Nicoll from Fujitsu Cyber ### References - https://www.silverstripe.org/download/security-releases/cve-2025-30148


Mitigations:

Architectural layers (MAESTRO):