CVE-2026-34744: MantisBT has an authorization bypass that allows reading attachments after losing access to a private issue

May 11, 2026 (updated June 5, 2026)

MantisBT permits a user to list and download their own attachments from an Issue created by another user, even after that Issue becomes private and direct access to it is denied.

References

github.com/advisories/GHSA-rmp5-5jj7-gmvf
github.com/mantisbt/mantisbt/commit/de7bdeec36de066235e38a77bf056917d951c84d
github.com/mantisbt/mantisbt/security/advisories/GHSA-rmp5-5jj7-gmvf
mantisbt.org/bugs/view.php?id=36977
nvd.nist.gov/vuln/detail/CVE-2026-34744

Code Behaviors & Features

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