Cross-site scripting in MantisBT - CVE-2026-34463
Published: November 6, 2026
Vulnerability identifier: #VU159807
CSH Severity: Low
CVSS v4: 4.8 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N]
CVE-ID: CVE-2026-34463
CWE-ID: CWE-79
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows an administrator to inject stored HTML into MantisBT's issue cloning form, enabling cross-site scripting.
The vulnerability exists due to insufficient escaping of the source project name in bug_report_page.php when cloning an issue from a project other than the current one. An administrator can set a malicious project name that injects attacker-controlled content when a user opens the affected clone form.
Affected software
MantisBT
How to mitigate CVE-2026-34463
Install security update from vendor's website.
MantisBT - update to 2.28.2