Alls perm 4,got hacked

[area9]

Wapmasters i use wapdesire sum1 hacked my site he just make allz perm=4 and changed alls password same! How did he do that?how to prevent it?pls post here

[area9]

Thank u riderz bro for ur helpful reply . .

Added after 2 minutes:

I have already us anti injection codes and from the topic 'how to secure all lavalair by subzero' i abide all those things but still he did that! Riderz bro what sud i do n0w?

[something else]

This topic comes up time and time again.... ALL the answers to your problem are posted so many times in this forum....
use the search button use ALL of the protection methods ...
if all else fails use a different script