Vulnerability 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. 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)
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://api.nuget.optimizely.com/packages/episerver.cms.core/11.21.4#
- https://api.nuget.optimizely.com/packages/episerver.cms.core/12.22.1#
- https://r.sec-consult.com/optimizely
- http://seclists.org/fulldisclosure/2025/Aug/18
FAQ
What is CVE-2025-27800?
CVE-2025-27800 is a vulnerability with a CVSS score of 4.8 (MEDIUM). 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 Java...
How severe is CVE-2025-27800?
CVE-2025-27800 has been rated MEDIUM with a CVSS base score of 4.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-27800?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.