FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. Prior to 1.8.212, FreeScout does not take the limit_user_customer_visibility parameter into account when merging customers. This vulnerability is fixed in 1.8.212.
https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-j6v9-22vq-53vh
https://github.com/freescout-help-desk/freescout/commit/b395a1179117af5e2df704c6bad71feeb301b4ce