CVE-2026-42071: MantisBT: Private Bugnote Attachment Content Leak via REST API

Severity: high (CVSS 7.2 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-862

Description

Mantis Bug Tracker (MantisBT) is an open source issue tracker. From 2.23.0 to 2.28.1, a missing authorization check in MantisBT's file visibility function allows any authenticated user (REPORTER+) to download attachments on private bugnotes they should not be able to access, via the REST API endpoint GET /api/rest/issues/{id}/files and SOAP API mc_issue_attachment_get endpoint. This vulnerability is fixed in 2.28.2.

Affected products

mantisbt: from 2.23.0, < 2.28.2

References

https://github.com/mantisbt/mantisbt/commit/029d9d203d9e4ae96b3e59d552fa7395cc1e5071
https://github.com/mantisbt/mantisbt/security/advisories/GHSA-pw5x-2mf9-3xc8
https://mantisbt.org/bugs/view.php?id=27039
https://mantisbt.org/bugs/view.php?id=36985
https://mantisbt.org/bugs/view.php?id=37092

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