Stored XSS Vulnerability in Optimizely Episerver Content Management System
CVE-2025-27802

4.8MEDIUM

Key Information:

Vendor

Optimizely

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

What is CVE-2025-27802?

The Optimizely Episerver Content Management System (CMS) is susceptible to multiple stored cross-site scripting (XSS) vulnerabilities. These weaknesses can be exploited by authenticated users, specifically those with 'WebEditor' roles, to inject arbitrary JavaScript code into text fields within the CMS. Once embedded, this malicious code executes in the browsers of users accessing the previewed pages, potentially leading to unauthorized access and data compromise.

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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://api.nuget.optimizely.com/packages/episerver.cms.c...
patch
https://api.nuget.optimizely.com/packages/episerver.cms.c...
patch
https://r.sec-consult.com/optimizely
third-party-advisory

CVSS V4

Score:
4.8
Severity:
MEDIUM
Confidentiality:
None
Integrity:
Low
Availability:
Low
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
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