CVE-2026-40496: Freescout

Critical severity, CVSS 9.1. EPSS: 0.5% chance of exploitation in the next 30 days.

FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.213, attachment download tokens are generated using a weak and predictable formula: `md5(APP_KEY + attachment_id + size)`. Since attachment_id is sequential and size can be brute-forced in a small range, an unauthenticated attacker can forge valid tokens and download any private attachment without credentials. Version 1.8.213 fixes the issue.

Affected products

• Freescout Freescout: before 1.8.213 (fixed in 1.8.213)

Published 2026-04-21. Last modified 2026-06-17.