The LinkedCustomFields plugin for MantisBT allows users to link values between two custom fields, creating linked drop-downs. Prior to version 2.0.1, cross-site scripting in the MantisBT LinkedCustomFields plugin allows Javascript execution, when a crafted Custom Field is linked via the plugin and displayed when reporting a new Issue or editing an existing one. This issue is fixed in version 2.0.1. As a workaround, one may utilize MantisBT's default Content Security Policy, which blocks script execution.
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.