You can delete firewall rules through the Kaspersky Security Center 13.2 Web Console.
To delete a firewall rule:
In the main window of the Web Console, select Devices → Managed devices.
Click the name of the device where Kaspersky IoT Secure Gateway 1000 is running. If the device name is not on the list, add it to the Managed devices group.
In the device properties window that opens, select the Applications tab.
Press Kaspersky IoT Secure Gateway.
This opens a window containing information about Kaspersky IoT Secure Gateway 1000.
Select the Application settings tab.
Select Network → Firewall.
This opens a table containing all the custom firewall rules.
Select the check box next to the rule that you want to delete.
Click the Delete button in the upper part of the firewall rules table.
The rule will be deleted from the firewall rules table.