Cross-site scripting in MantisBT - CVE-2026-33548
Published: November 6, 2026
Vulnerability identifier: #VU159791
CSH Severity: Low
CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N]
CVE-ID: CVE-2026-33548
CWE-ID: CWE-79
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote authenticated attacker with low privileges to inject HTML into another user's MantisBT Timeline.
The vulnerability exists due to improper escaping of historical tag names in the Timeline at my_view_page.php when tags have been renamed or deleted. A remote authenticated attacker with low privileges can supply a malicious tag name to execute arbitrary JavaScript when a victim views the affected Timeline and Content Security Policy settings permit execution.
Affected software
MantisBT
How to mitigate CVE-2026-33548
Install security update from vendor's website.
MantisBT - update to 2.28.2