gprs protocol issue

[fabiofabio]

good morning,
this morning I noticed a certain alert in the logs. the log that I show below with the respective firewall rule, points out to me that anyone who uses a tcp protocol of any type with the certain range of open ports can enter that server. is there a way to block access to the tcp-gprs protocol only? or is it possible to limit communications from certain ssid? also, did I correctly interpret what happened in that log? the alert simply warned me that someone used the kerberos protocol, right? any advice is welcome, thanks