Executive brief
Zammad is a web based open source helpdesk/customer support system. Prior to 7.1.2, the legacy destroy_form action on AttachmentsController deletes UploadCache Store records based solely on a user-supplied form_id without verifying that the requesting user owns those records. An authenticated attacker who learns another user's pending-upload UUID can silently remove temporary file uploads before the victim submits their ticket or article. This issue is fixed in version 7.1.2.