Vulnerability · Published Jul 28, 2025 · Assigned by SEC-VLab
CVE-2025-27802Stored Cross-Site Scripting in Episerver Content Management System (CMS) Edit Preview
Medium 4.8
In plain English
A medium-severity cross-site scripting in Episerver Content Management System (CMS) from Optimizely. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 30% of all known vulnerabilities).
Official description
The Episerver Content Management System (CMS) by Optimizely was affected by multiple Stored Cross-Site Scripting (XSS) vulnerabilities. This allowed an authenticated attacker to execute malicious JavaScript code in the victim's browser. RTE properties (text fields), which could be used in the "Edit" section of the CMS, allowed the input of arbitrary text. It was possible to input malicious JavaScript code in these properties that would be executed if a user visits the previewed page. Attackers needed at least the role "WebEditor" in order to exploit this issue. Affected products: Version 11.X: EPiServer.CMS.Core (<11.21.4) with EPiServer.CMS.UI (<11.37.5), Version 12.X: EPiServer.CMS.Core (<12.22.1) with EPiServer.CMS.UI (<11.37.3)
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Optimizely | Episerver Content Management System (CMS) | 11.x – before 11.21.412.x – before 12.22.1 |
Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N