Optimizely Episerver Content Management System up to 11.21.3/12.22.0 Admin Dashboard cross site scripting

Summaryinfo

A vulnerability identified as problematic has been detected in Optimizely Episerver Content Management System up to 11.21.3/12.22.0. Affected by this issue is some unknown functionality of the component Admin Dashboard. The manipulation leads to cross site scripting. This vulnerability is traded as CVE-2025-27800. It is possible to initiate the attack remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Optimizely Episerver Content Management System up to 11.21.3/12.22.0. It has been rated as problematic. This issue affects some unknown functionality of the component Admin Dashboard. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. The summary by CVE is:

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. The Admin dashboard offered the functionality to add gadgets to the dashboard. This included the "Notes" gadget. An authenticated attacker with the corresponding access rights (such as "WebAdmin") that was impersonating the victim could insert malicious JavaScript code in these notes that would be executed if the victim visited the dashboard. 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)

The weakness was shared by Kai Zimmermann. It is possible to read the advisory at support.optimizely.com. The identification of this vulnerability is CVE-2025-27800 since 03/07/2025. The exploitation is known to be easy. The attack may be initiated remotely. Additional levels of successful authentication are needed for exploitation. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

Upgrading to version 11.21.4 or 12.22.1 eliminates this vulnerability.

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Productinfo

Type

• Content Management System

Vendor

• Optimizely

Name

• Episerver Content Management System

Version

• 11.21.0
• 11.21.1
• 11.21.2
• 11.21.3
• 12.0
• 12.1
• 12.2
• 12.3
• 12.4
• 12.5
• 12.6
• 12.7
• 12.8
• 12.9
• 12.10
• 12.11
• 12.12
• 12.13
• 12.14
• 12.15
• 12.16
• 12.17
• 12.18
• 12.19
• 12.20
• 12.21
• 12.22.0

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

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Entryinfo

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