CVE-2026-40598
MantisBT has Potential Referer-Based Reflected HTML Injection / XSS in Tag Update Page
Mantis Bug Tracker (MantisBT) is an open source issue tracker. In versions 2.28.1 and below, improper escaping of the redirection page (retrieved from the request's Referer header) allows an attacker to inject HTML. While this is generally not directly actionable as modern browsers will URL-encode special characters, on some specific server configurations this could poison the cache, leading to cross-site scripting. This issue has been fixed in version 2.28.2.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
MantisBT has Potential Referer-Based Reflected HTML Injection / XSS in Tag Update Page
Mantis Bug Tracker (MantisBT) is an open source issue tracker. In versions 2.28.1 and below, improper escaping of the redirection page (retrieved from the request's Referer header) allows an attacker to inject HTML. While this is generally not directly actionable as modern browsers will URL-encode special characters, on some specific server configurations this could poison the cache, leading to cross-site scripting. This issue has been fixed in version 2.28.2.
- Record
CVE-2026-40598- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2026-31494
Mantis Bug Tracker (MantisBT) is an open source issue tracker. In versions 2.28.1 and below, improper escaping of the redirection page (retrieved from the request's Referer header) allows an attacker to inject HTML. While this is generally not directly actionable as modern browsers will URL-encode special characters, on some specific server configurations this could poison the cache, leading to cross-site scripting. This issue has been fixed in version 2.28.2.
- Record
EUVD-2026-31494- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-6jh4-47v2-4g37
MantisBT has Potential Referer-Based Reflected HTML Injection / XSS in Tag Update Page
Improper escaping of the redirection page (retrieved from the request's Referer header) allows an attacker to inject HTML.
While this is generally not directly actionable as modern browsers will URL-encode special characters, on some specific server configurations this could poison the cache, leading to cross-site scripting.
Impact
Cross-site scripting (XSS).
Patches
- b1ebc57763f104eb5f541b7b4d1ce6948168abd9
Workarounds
None
Credits
Thanks to siunam (Tang Cheuk Hei) for discovering and responsibly reporting the issue.
- Record
GHSA-6jh4-47v2-4g37- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
Mantis Bug Tracker (MantisBT) is an open source issue tracker. In versions 2.28.1 and below, improper escaping of the redirection page (retrieved from the request's Referer header) allows an attacker to inject HTML. While this is generally not directly actionable as modern browsers will URL-encode special characters, on some specific server configurations this could poison the cache, leading to cross-site scripting. This issue has been fixed in version 2.28.2.
- Record
CVE-2026-40598- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/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 - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
MantisBT has Potential Referer-Based Reflected HTML Injection / XSS in Tag Update Page
Mantis Bug Tracker (MantisBT) is an open source issue tracker. In versions 2.28.1 and below, improper escaping of the redirection page (retrieved from the request's Referer header) allows an attacker to inject HTML. While this is generally not directly actionable as modern browsers will URL-encode special characters, on some specific server configurations this could poison the cache, leading to cross-site scripting. This issue has been fixed in version 2.28.2.
- Record
CVE-2026-40598- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSVGHSA-6jh4-47v2-4g37
MantisBT has Potential Referer-Based Reflected HTML Injection / XSS in Tag Update Page
Improper escaping of the redirection page (retrieved from the request's Referer header) allows an attacker to inject HTML.
While this is generally not directly actionable as modern browsers will URL-encode special characters, on some specific server configurations this could poison the cache, leading to cross-site scripting.
Impact
Cross-site scripting (XSS).
Patches
- b1ebc57763f104eb5f541b7b4d1ce6948168abd9
Workarounds
None
Credits
Thanks to siunam (Tang Cheuk Hei) for discovering and responsibly reporting the issue.
- Record
GHSA-6jh4-47v2-4g37- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
mantisbt/mantisbtPackagist |
through 2.28.1 | 2.28.2 |
mantisbt/mantisbtPackagist |
before 2.28.2, plus listed versions 2.10.02.10.12.11.02.11.12.12.0 Show 45 moreShow less2.12.12.12.22.13.02.13.12.13.22.14.02.15.02.15.12.16.02.16.12.17.02.17.12.17.22.18.02.18.12.19.02.19.12.20.02.20.12.21.02.21.12.21.22.21.32.22.02.22.12.22.22.23.02.23.12.24.02.24.12.24.22.24.32.24.42.24.52.25.02.25.12.25.22.25.32.25.42.25.52.25.62.25.72.25.82.26.02.26.1 |
2.28.2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-40598 is a medium vulnerability (CVSS 6.9) in Mantisbt, published May 11, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.45%, the 39th percentile. Fixed in mantisbt/mantisbt 2.28.2.
References
github.com/mantisbt/mantisbt/security/advisories/GHSA-6jh4-47v2-4g37
mantisbt.org/bugs/view.php?id=37017
nvd.nist.gov/vuln/detail/CVE-2026-40598
Left out here: 26 versions. The JSON record has them.