CVE-2025-27802

MEDIUM

Optimizely Episerver CMS 11.x < 11.21.4 and 12.x < 12.22.1 - Authenticated Stored Cross-Site Scripting in RTE Properties

Title source: llm
STIX 2.1

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)

Scores

CVSS v3 4.8
EPSS 0.0033
EPSS Percentile 24.6%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-79
Status published
Products (2)
Optimizely/Episerver Content Management System (CMS) 11.x - 11.21.4
Optimizely/Episerver Content Management System (CMS) 12.x - 12.22.1
Published Jul 28, 2025
Tracked Since Feb 18, 2026