Ettercap is a multipurpose sniffer/interceptor/logger for switched LAN. It supports active and passive dissection of many protocols (even ciphered ones) and includes many feature for network and host analysis.
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Cool Features: Characters injection in an established connection : you can inject character to server (emulating commands) or to client (emulating replies) maintaining the connection alive !!
SSH1 support : you can sniff User and Pass, and even the data of an SSH1 connection. ettercap is the first software capable to sniff an SSH connection in FULL-DUPLEX
HTTPS support : you can sniff http SSL secured data... and even if the connection is made through a PROXY
Remote traffic through GRE tunnel: you can sniff remote traffic through a GRE tunnel from a remote cisco router and make mitm attack on it
PPTP broker: you can perform man in the middle attack against PPTP tunnels
Plug-ins support : You can create your own plugin using the ettercap's API.
Paket filtering/dropping: You can set up a filter that search for a particular string (even hex) in the TCP or UDP payload and replace it with yours or drop the entire packet.
OS fingerprint: you can fingerprint the OS of the victim host and even its network adapter
Kill a connection: from the connections list you can kill all the connections you want
Passive scanning of the LAN: you can retrive infos about: hosts in the lan, open ports, services version, type of the host (gateway, router or simple host) and extimated distance in hop.
Check for other poisoners: ettercap has the ability to actively or passively find other poisoners on the LAN
Bind sniffed data to a local port: you can connect to that port with a client and decode unknown portocols or inject data to it (only in arp based mode)
Port Stealing: a new method to sniff on switched LAN without ARP poisoning...
Platform: Linux 2.0.x Linux 2.2.x Linux 2.4.x FreeBSD 4.x OpenBSD 2.[789] 3.0 NetBSD 1.5 Mac OS X (darwin 1.3 1.4 5.1) Windows 9x/NT/2000/XP Solaris 2.x
