Headline
GHSA-rhx4-hvx9-j387: Silverstripe Framework has a XSS vulnerability in HTML editor
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
Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.