DNN (formerly DotNetNuke) is an open-source web content management platform (CMS) in the Microsoft ecosystem. Prior to versions 9.13.10 and 10.2.0, a module could install with richtext in its description field which could contain scripts that will run for user in the Persona Bar. Versions 9.13.10 and 10.2.0 contain a fix for the issue.
https://github.com/dnnsoftware/Dnn.Platform/security/advisories/GHSA-9r3h-mpf8-25gj