CVE-2026-42070: MantisBT: Authorization Bypass in Bugnote Editing via Issue Update API

Severity: medium (CVSS 5.3 v4.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-28 · updated 2026-06-17
Weakness: CWE-863

Description

Mantis Bug Tracker (MantisBT) is an open source issue tracker. Prior to 2.28.2, the mc_issue_update() function in MantisBT allows users having update_bug_threshold access (UPDATER, with default settings) to edit, change view state, and modify time tracking on bugnotes belonging to other users — bypassing the default DEVELOPER (level 55) threshold required by the dedicated mc_issue_note_update() function. This vulnerability is fixed in 2.28.2.

Affected products

mantisbt: before 2.28.2

References

https://github.com/mantisbt/mantisbt/commit/6e58fae4f22efdc3987f903c8ba2611de17a9435
https://github.com/mantisbt/mantisbt/security/advisories/GHSA-pq86-j2c2-47f6
https://mantisbt.org/bugs/view.php?id=37089
https://mantisbt.org/bugs/view.php?id=37093

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