FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.214, the phone-conversation creation flow accepts attacker-controlled customer_id, name, to_email, and phone values and resolves the target customer in the backend without enforcing mailbox-scoped customer visibility. As a result, a low-privileged agent who can create a phone conversation in Mailbox A can bind the new Mailbox A phone conversation to a hidden customer from Mailbox B and add a new alias email to that hidden customer record by supplying to_email. Version 1.8.214 fixes the vulnerability.
Exploitability
AV:NAC:LPR:LUI:NScope
S:UImpact
C:LI:HA:N7.1/CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:NOther