CVE-2026-40596 json
MantisBT is vulnerable to XSS and potential account takeover via user font family preference update
published 5mo ago modified last mo. also EUVD-2026-31492 , GHSA-j3v9-553h-x28j
- cvss
- 7.2
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 36%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- packagist mantisbt/mantisbt 2.28.2
- mantisbt mantisbt 2.28.2
Is CVE-2026-40596 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 5mo ago
Exploit prediction
0.42% chance of exploitation in the next 30 days, higher than 36% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 7.2 | 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 |
| CNA | 4.0 | 7.2 | 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| packagist | mantisbt/mantisbt | >=2.11.0, <2.28.2 |
2.28.2 |
Affected products
- mantisbt mantisbt
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/mantisbt/mantisbt/commit/9e8409cdd979eba86ef532756fc47c1d8112d22d
web
-
github.com
/mantisbt/mantisbt/security/advisories/GHSA-j3v9-553h-x28j
web
-
github.com
/mantisbt/mantisbt/security/advisories/GHSA-9c3j-xm6v-j7j3
web
-
mantisbt.org
/bugs/view.php?id=37011
web
-
mantisbt.org
/bugs/view.php?id=37016
web
-
nvd.nist.gov
/vuln/detail/CVE-2026-40596
advisory
-
github.com
/mantisbt/mantisbt
package
Sources
- CVE List CVE-2026-40596
- GitHub Advisory GHSA-j3v9-553h-x28j
- NVD CVE-2026-40596
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.