MantisBT has a Private Bugnote Attachment Content Leak via REST API

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

7.2 · CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N · score source

EPSS

• CVE-2026-42071: 0.26% estimated exploitation activity in the next 30 days; percentile 17.82 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

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 mcissueattachmentget endpoint. Impact - REPORTER (access level 25) can view file attachments that were uploaded to private bugnotes by DEVELOPER/MANAGER/ADMIN users - Private bugnotes are intended for internal developer discussion; their attachments (logs, screenshots, patches) should be equally protected - The web UI is NOT affected — it filters through bugnotegetallvisiblebugnotes() first Patches - 029d9d203d9e4ae96b3e59d552fa7395cc1e5071 Workarounds None Credits Thanks to the following security researchers for independently discovering and responsibly reporting the issue. - Vishal Shukla - Tristan Madani (@TristanInSec) from Talence Security - Tang Cheuk Hei (@siunam321) This advisory's contents was largely copied from…

Published by the source

11 May 2026, 19:39 UTC

Last modified by the source

9 Jun 2026, 10:23 UTC

Source last checked

26 Oct 2026, 14:48 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-pw5x-2mf9-3xc8

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# Patch Next advisory brief: CVE-2026-42071

Advisory: MantisBT has a Private Bugnote Attachment Content Leak via REST API
IDs: CVE-2026-42071, GHSA-pw5x-2mf9-3xc8
Record: https://patchnext.com/advisories/cve-2026-42071 (revision 1, source checked 26 Oct 2026, 14:48 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.2)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: mantisbt/mantisbt 2.28.2. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist mantisbt/mantisbt: affected >= 2.23.0, <= 2.28.1; fixed in 2.28.2

## Suggested inspection (read-only)
- Packagist mantisbt/mantisbt: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on mantisbt/mantisbt.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-pw5x-2mf9-3xc8 (GitHub-reviewed advisory GHSA-pw5x-2mf9-3xc8 lists affected ranges: Packagist mantisbt/mantisbt >=2.23.0 <=2.28.1)

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