Executive brief
MantisBT is a popular open-source bug tracking system. A security vulnerability allows an authenticated user to upload an image with a specially crafted filename that executes malicious scripts when other users view the bug report's export page. This could lead to unauthorized actions being performed in the context of the victim's session, though the impact is partially mitigated by the application's security policies.
Technical details
A stored cross-site scripting (XSS) vulnerability exists in MantisBT due to missing output encoding in 'print_all_bug_page_word.php'. An authenticated attacker can upload an image attachment with a crafted filename (e.g., containing a double quote and an 'onload' event handler). When a user views the HTML export page (type_page=html&export=1), the filename is improperly rendered within an IMG tag's 'alt' attribute, allowing the attacker to break out of the attribute and execute arbitrary JavaScript. The vulnerability is mitigated by the application's Content Security Policy (CSP). The issue is fixed in version 2.28.4.
Affected products
- MantisBT MantisBT <= 2.28.3
Timeline
- 2026-07-15: disclosed
- 2026-07-15: patched
- 2026-07-15: advisory
References
- https://api.github.com/users/dracosectech-code
- https://github.com/dracosectech-code
- https://api.github.com/users/dracosectech-code/gists%7B/gist_id%7D
- https://api.github.com/users/dracosectech-code/repos
- https://avatars.githubusercontent.com/u/266971538?v=4
- https://api.github.com/users/dracosectech-code/events%7B/privacy%7D