Mantis Bug Tracker (MantisBT) is an open source issue tracker. Versions 2.28.1 and prior permit a user to list and download their own attachments from an Issue created by another user even after it becomes private, bypassing read access revocation. The loss of confidentiality caused by this vulnerability is minimal, considering that only attachments previously uploaded by the user themselves remain accessible. This issue has been fixed in version 2.82.2.