What is CVE-2026-39960?

CVE-2026-39960 is a medium-severity vulnerability in Mantisbt, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-05-20.

How severe is CVE-2026-39960?

Medium severity. CVSS v3 base score is 5.4 out of 10.

XSS in Mantisbt

CVE-2026-39960

Mantis Bug Tracker (MantisBT) is an open source issue tracker. Versions 2.28.1 and below contain flawed logic that causes improper escaping of a textarea custom field's contents in the Update Issue page, (bug_update_page.php) allowing an a…

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.000 (10.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

Affected products

Mantisbt — versions < 2.28.2

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

security-advisories@github.com (x_refsource_CONFIRM)
security-advisories@github.com (x_refsource_MISC)

Frequently asked questions

What is CVE-2026-39960?: CVE-2026-39960 is a medium-severity vulnerability in Mantisbt, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-05-20.
How severe is CVE-2026-39960?: Medium severity. CVSS v3 base score is 5.4 out of 10.