Defense Against the Dark Arts ARP poisoning –Flood network with ARP responses –Typically: fool hosts into thinking that the Internet gateway is at your MAC address instead of the real one TCP hijacking –Inject, Delete or change data into a TCP stream (and fix up packets so no one notices) –Example: HTTP user logs in, then you change a transaction in a HTTP stream, add a transaction to HTTP You request to withdraw $100, attacker generates a withdrawal for $1 and a check for $99 to his henchman –Example: SSL Renegotiate attack (advanced topic)SSL Renegotiate attack MITM intercepts initial SSL handshake request (Client Hello) MITM opens SSL handshake to destination and sends initial request, followed by a renegotiation request MITM lets user request proceed as renegotiation