I’ll try to assist you
If you are wanting to completely block these address’s please use “Blocked Zones” (tab) for simple and easy way to block IP Address’s/Hostnames etc …
Note; You must move your rule on the top of list to be applied first (The List of rules are prioritized from top (first) to bottom (last)
As for the situation you presented may
What is your private IP Address?
Reason I’m asking, is because if your Private IP Address is 192.168 then the following rule that you posted would not work; because 192 does not apply to 125 through 125;
Try
Log as a firewall event if this rule is fired (enable)
Action: Block
Protocol: ICMP
Direction: Out
Description: Block ICMP Echo Request
Source Address: Network Zone (Choose Your Network Zone Defined in “Network Zones” tab)
Destination Address: Any
ICMP Details: ICMP Echo Request
Then Try to ping; as a result you cannot ping anyone
May i ask what you are trying to accomplish; see if i can assist you further?