Cross-site scripting (XSS) vulnerability in MantisBT before 1.2.2 allows remote authenticated users to inject arbitrary web script or HTML via an HTML document with a .gif filename extension, related to inline attachments.
Mantis 1.1.x through 1.1.2 and 1.2.x through 1.2.0a2 does not set the secure flag for the session cookie in an https session, which can cause the cookie to be sent in http requests and make it easier for remote attackers to capture this cookie.