GitHub Advisoryadvisory · Packagist

GHSA-j3v9-553h-x28j MantisBT is Vulnerable to XSS leading to account takeover via updating a user's font family preference

HIGH Published 2026-05-11 Modified 2026-06-08 Official page ↗
Aliases
CVE-2026-40596
Ecosystem
Packagist
Packages
mantisbt/mantisbt
Severity
High
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:H/VI:L/VA:L/SC:H/SI:H/SA:L
Weaknesses
CWE-79
Reviewed
2026-05-11

Affected packages

• Packagist mantisbt/mantisbt: >= 2.11.0, < 2.28.2 → fixed in 2.28.2

Description

Any authenticated user can inject arbitrary HTML via updating their account's font family. Impact Cross-site scripting. The injected payload will be reflected in every MantisBT page. Leveraging another vulnerability (CSP bypass, see GHSA-9c3j-xm6v-j7j3), the attacker could achieve account takeover. Patches • 9e8409cdd979eba86ef532756fc47c1d8112d22d Workarounds None Credits Thanks to siunam (Tang Cheuk Hei) for discovering and responsibly reporting the issue.

Related

Alias · CVE (1)

  • CVE-2026-40596 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