CVE-2026-40596
CWE-79Published: May 22, 2026· Updated: May 22, 2026
Official Description
Mantis Bug Tracker (MantisBT) is an open source issue tracker. Versions 2.11.0 through 2.28.1 allow any authenticated user to inject arbitrary HTML by updating their account's font family. Upon exploitation, an XSS payload would be reflected on every MantisBT page. Leveraging another vulnerability (CSP bypass, see GHSA-9c3j-xm6v-j7j3), the attacker could achieve account takeover. This issue has been fixed in version 2.28.2.
Technical Analysis
CVE-2026-40596 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.
CVSS v3.1 Vector Breakdown
Exploit & PoC Resources
All References (5)
Quick Facts
Related CVEs (CWE-79)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-40596 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts