MantisBT Vulnerable to Exposure of Sensitive Information to an Unauthorized Actor

MantisBT (Mantis Bug Tracker) is an open source issue tracker. If an issue references a note that belongs to another issue that the user doesn't have access to, then it gets hyperlinked. Clicking on the link gives an access denied error as expected, yet some information remains available via the link, link label, and tooltip. This can result in disclosure of the existence of the note, the note author name, the note creation timestamp, and the issue id the note belongs to. Version 2.26.2 contains a patch for the issue. No known workarounds are available.