Mastering Firewall Packet Detection with Wireshark: Filtering and Port Scanning Techniques

To use Wireshark for firewall packet detection, open the application and enter the filter “ip.src == [IP] && ip.ttl < 255”. This is because packets forged by the firewall typically have a TTL of 255, whereas genuine packets should have a TTL of 56. This filter helps in directly excluding the fake packets. Next, use a port scanner to scan all ports of the target IP. Finally, focus on identifying the ports that remain unfiltered after applying the scan.

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firewall packet detection />firewall packet detection