via SSH or Remote Desktop), and if so sets a default capture filter that should block out the remote session traffic. Wireshark tries to determine if it's running remotely (e.g.

Please change the network filter to reflect your own network.ĭst port 135 or dst port 445 or dst port 1433 and tcp & (tcp-syn) != 0 and tcp & (tcp-ack) = 0 and src net 192.168.0.0/24 This filter is independent of the specific worm instead it looks for SYN packets originating from a local network on those specific ports. Many worms try to spread by contacting other hosts on ports 135, 445, or 1433. It is the signature of the welchia worm just before it tries to compromise a system. icmp=icmp-echo and ip=92 and icmp=0xAAAAAAAA The filter looks for an icmp echo request that is 92 bytes long and has an icmp payload that begins with 4 bytes of A's (hex).dst port 135 and tcp port 135 and ip=48.ones that describe or show the actual payload?) port 80 and tcp & 0xf0) > 2):4] = 0x47455420īlaster and Welchia are RPC worms.From Jefferson Ogata via the tcpdump-workers mailing list. (tcp > 1500 and tcp 1500 and tcp > 2' figures out the TCP header length.host and not (port 80 or port 25) host and not port 80 and not port 25.

The display filter can be changed above the packet list as can be seen in this picture:Ĭapture only traffic to or from IP address 172.18.5.4:Ĭapture traffic to or from a range of IP addresses:Ĭapture traffic from a range of IP addresses:Ĭapture traffic to a range of IP addresses:Ĭapture non-HTTP and non-SMTP traffic on your server (both are equivalent): In the main window, one can find the capture filter just above the interfaces list and in the interfaces dialog. Display filters on the other hand do not have this limitation and you can change them on the fly.

The latter are used to hide some packets from the packet list.Ĭapture filters are set before starting a packet capture and cannot be modified during the capture. The former are much more limited and are used to reduce the size of a raw packet capture. Capture filters (like tcp port 80) are not to be confused with display filters (like tcp.port = 80).

Wireshark display filters examples