Quick answers
- Is CVE-2026-42071 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-42071 being exploited in the wild.
- How severe is CVE-2026-42071?
- High severity, with a CVSS score of 4, published 28 May 2026.
- Which products and versions are affected?
- MantisBT >= 2.23.0, <= 2.28.1, 2.23.0 to 2.28.1; mantisbt/mantisbt (Packagist) >= 2.23.0, <= 2.28.1, ECOSYSTEM:introduced=2.23.0,fixed=2.28.2.
- Is there a fix for CVE-2026-42071?
- Yes. mantisbt/mantisbt (Packagist): upgrade to 2.28.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-42071 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-42071?
- Check whether you run MantisBT or mantisbt/mantisbt (Packagist) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- mantisbt/mantisbt (Packagist): upgrade to 2.28.2 or later
composer require mantisbt/mantisbt:^2.28.2
Technical details
A missing authorization check in MantisBT's file visibility logic allows authenticated users with REPORTER-level access or higher to bypass intended restrictions on private bugnotes. While the web interface correctly filters these attachments, the REST API (GET /api/rest/issues/{id}/files) and SOAP API (mc_issue_attachment_get) endpoints do not properly validate if the requesting user has permission to view files attached to private notes. An attacker can exploit this to download sensitive internal documentation, logs, or patches. The issue is addressed in version 2.28.2 by implementing proper authorization checks in the affected API functions.
Affected products
- MantisBT MantisBT >= 2.23.0, <= 2.28.1
Identifiers
- CVE-2026-42071
- GHSA-pw5x-2mf9-3xc8
Timeline
- 2026-05-09: disclosed
- 2026-05-11: advisory: GitHub Advisory published
- 2026-05-28: advisory: NVD published