When cloning an issue originating from a Project other than the current one, the clone form (bug_report_page.php) prepends the source Project name before the category selector without proper escaping, allowing an attack…
| CVE ID | CVE-2026-34463 |
| Vendor | composer |
| Affected Product | mantisbt/mantisbt |
| Vulnerability Type | Vulnerability |
| CVSS Score | 7.5 (HIGH) |
| Actively Exploited | ❌ No known exploitation |
| Patch Status | See Vendor Advisory → |
| Reported By | CYBERDUDEBIVASH SENTINEL APEX Intelligence (via github_advisories) |
When cloning an issue originating from a Project other than the current one, the clone form (bug_report_page.php) prepends the source Project name before the category selector without proper escaping, allowing an attacker able to to inject HTML if they can set the Project's name (which typically requires *manager* or *administrator* access level).
Cross-site scripting (XSS). This is mitigated by Content Security Policy which restricts scripts execution.
Make sure Project names do not contain any HTML tags.
Thanks to Vishal Shukla for discovering and responsibly reporting the issue. The vulnerability was also identified and independently reported by @siunam321 (Tang Cheuk Hei), prior to this Adviso
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