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

May 11, 2026 (updated June 9, 2026)

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.

References

github.com/advisories/GHSA-pq86-j2c2-47f6
github.com/mantisbt/mantisbt/commit/6e58fae4f22efdc3987f903c8ba2611de17a9435
github.com/mantisbt/mantisbt/security/advisories/GHSA-pq86-j2c2-47f6
mantisbt.org/bugs/view.php?id=37089
mantisbt.org/bugs/view.php?id=37093
nvd.nist.gov/vuln/detail/CVE-2026-42070

Code Behaviors & Features

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