GitHub Advisoryadvisory · Packagist

GHSA-fvjf-68wh-rwp2 MantisBT is Vulnerable to Stored HTML Injection/XSS in Clone Issue Form

HIGH Published 2026-05-11 Modified 2026-06-05 Official page ↗
Aliases
CVE-2026-34463
Ecosystem
Packagist
Packages
mantisbt/mantisbt
Severity
High
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Weaknesses
CWE-79
Reviewed
2026-05-11

Affected packages

• Packagist mantisbt/mantisbt: < 2.28.2 → fixed in 2.28.2

Description

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). Impact Cross-site scripting (XSS). This is mitigated by Content Security Policy which restricts scripts execution. Patches • df22697ae497ddd93f3d9132fdf4979db8d081cd Workarounds Make sure Project names do not contain any HTML tags. Credits 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 Advisory's publication.

Related

Alias · CVE (1)

  • CVE-2026-34463 Mantis Bug Tracker (MantisBT) is an open source issue tracker. vulnerability

Weakness · CWE (1)

  • CWE-79 Improper Neutralization of Input During Web Page Generation weakness

References