Stored Cross-Site Scripting Vulnerabilities in Episerver CMS by Optimizely
CVE-2025-27801

4.6MEDIUM

Key Information:

Vendor

Optimizely

Status
Episerver Content Management System (cms)
Vendor
CVE Published:
28 July 2025

What is CVE-2025-27801?

The Episerver Content Management System by Optimizely suffers from multiple Stored Cross-Site Scripting vulnerabilities. Authenticated attackers with the WebEditor role can exploit these vulnerabilities to upload SVG files containing malicious JavaScript code. When a user accesses the direct URL of the uploaded content, the malicious script is executed in their browser, potentially compromising sensitive information and user experience.

Affected Version(s)

Episerver Content Management System (CMS) 11.x < 11.21.4

Episerver Content Management System (CMS) 12.x < 12.22.1

References

https://support.optimizely.com/hc/en-us/articles/30886353...
patch
https://support.optimizely.com/hc/en-us/articles/37757063...
patch

CVSS V4

Score:
4.6
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Kai Zimmermann, SEC Consult Vulnerability Lab
Felix Beie, SEC Consult Vulnerability Lab
.