CVE-2026-42071 MantisBT: Private Bugnote Attachment Content Leak via REST API
Authenticated users can download private bugnote attachments via API endpoints due to missing authorization checks in MantisBT.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-42071?
CVE-2026-42071 is a high-severity missing authorization vulnerability in mantisbt, published on 28 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Weakness: CWE-862
Which versions are affected by CVE-2026-42071?
2 open source packages ship an affected version, including mantisbt/mantisbt.
| Package | Affected | Fixed in |
|---|---|---|
mantisbt/mantisbt Packagist | From 2.23.0 | 2.28.2 |
mantisbt/mantisbt Packagist | From 2.23.0 | 2.28.2 |
How do I fix CVE-2026-42071?
Upgrade mantisbt/mantisbt to 2.28.2 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-42071 being exploited?
There is no known exploitation of CVE-2026-42071 in the wild and no public exploit code.
Sources
Also known as GHSA-pw5x-2mf9-3xc8.