Advance Web Hacking

this article is about web hacking, to practice i use DVWA (Damn Vulnerable Web Application) as victim, DVWA provide any web vulnerabilities. in this article i try to exploits command execution Vulnerability in DVWA.
firts open DVWA from your browser

then login  using username : admin and password : password, its default. then  change DVWA Security to Medium

then choose command execution

then try to execute command, i type localhost and submit

then i try to execute nc

then i try to run nc in ubuntu

then i search exploit linux in exploits-db, in here my backtrack use kernel 2.6.39

but this file not work normally,,
to be continued,,