Skip to content
OpenAdvisories
Medium · 4.8 CVE-2025-27802 EUVD-2025-22862GHSA-hwcj-2grf-hc24

Stored Cross-Site Scripting in Episerver Content Management System (CMS) Edit Preview

Published Jul 28, 2025 · Updated Nov 3, 2025 · Assigned by SEC-VLab

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

VendorProductAffectedFixed
Optimizely Episerver Content Management System (CMS) 11.x – < 11.21.4, 12.x – < 12.22.1 11.21.4

References