FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.214, the Change Customer modal exposes a “Create a new customer” flow via POST /customers/ajax with action=create. Under limited visibility, the endpoint drops unique-email validation. If the supplied email already belongs to a hidden customer, Customer::create() reuses that hidden customer object and fills empty profile fields from attacker-controlled input. Version 1.8.214 fixes the vulnerability.
https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-wjw4-8xg6-342m
https://github.com/freescout-help-desk/freescout/releases/tag/1.8.214
https://github.com/freescout-help-desk/freescout/commit/b3d7611e6e173ed8a5e525b791deb6b32cf1ce62