sshtrix is a very fast multithreaded SSH login cracker. It supports SSHv1 and SSHv2. sshtrix was designed to automate rapid bruteforce attacks against SSH authentification screens. Unlike other public tools, the aim is to keep it simple, stable, fast and modular. With its clean code design, it is easy to extend the code to a framework or to fork it against protocols of your choice.
Created by Justin Grevich at UC San Diego

/* help and usage */
void usage()
sshtrix -h/-I/-R -m [options]\n\
sshtrix -h/-I/-R -l/-L -k/-K [options]\n\
-h - target host to attack (default\n\
-I - define target ip address range\n\
-R - target list filename (one host per line). can also contain\n\
port numbers seperated with colon (e.g.\n\
-p - SSH server port (default 22)\n\
-m - colon separated login file (e.g. user:pass)\n\
-l - user list (one username per line)\n\
-k - pass list (one password per line)\n\
-L - username string\n\
-K - password string\n\
-D - use sshtrix's default wordlist for usernames and passwords\n\
-O - print out sshtrix's default wordlist and number of entries\n\
-c - connect timeout (default 3s)\n\
-w - delay before next try (default 0s)\n\
-t - num threads of parallel connects (default 4)\n\
-f - write found login pairs to file (default stdout)\n\
-e - exit after first valid login (default off)\n\
-s - print found logins immediatelly (default off)\n\
-v - verbose mode (default quiet)\n\
-V - show sshtrix version\n\
-H - show help and usage\n\n");
sshtrix -R host.lst -m login.lst\n\
sshtrix -h -D\n\
sshtrix -I -l user.lst -K pass123\n\
sshtrix -h -L noptrix -k pass.lst\n");