CVE-2026-34754: MantisBT allows unauthorized users to upload attachments to restricted issues via REST API

Severity: medium (CVSS 4.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-20 · updated 2026-07-24
Weakness: CWE-284

Description

Mantis Bug Tracker (MantisBT) is an open source issue tracker. Versions 2.28.1 and prior allow an authenticated user to upload attachments to private Issues they are not authorized to access. This issue has been fixed in version 2.28.2.

Affected products

mantisbt: before 2.28.2

References

https://github.com/mantisbt/mantisbt/commit/b262b4d2835b81394d75356dead66e52a6275206
https://github.com/mantisbt/mantisbt/security/advisories/GHSA-h4x5-gvx6-3rwc
https://mantisbt.org/bugs/view.php?id=36976

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