Executive brief
FreeScout is an open-source help desk and shared inbox platform used by teams to manage customer communications. A security flaw allows former team members to permanently delete internal notes they previously created, even after their access to the specific mailbox has been revoked. This could lead to the loss of sensitive internal documentation or the destruction of audit trails by disgruntled or former employees.
Technical details
A missing authorization check in the ThreadPolicy::delete policy allows users to delete internal notes (threads of type NOTE) based solely on authorship. The vulnerable component fails to verify if the requesting user still maintains active membership or access rights to the mailbox containing the conversation. An attacker with low-privileged credentials can exploit this by sending a crafted POST request to the AJAX conversation endpoint with a specific thread ID. This results in permanent deletion of the note from the database, bypassing intended access revocations. The issue is resolved in version 1.8.221 by adding a mailbox membership verification step to the deletion logic.
Affected products
- FreeScout FreeScout < 1.8.221
Timeline
- 2026-05-28: advisory: GitHub Security Advisory published
- 2026-05-29: disclosed: CVE published to NVD
- 2026-05-29: patched: Fix released in version 1.8.221