Hack a centos linux box

HI,
I have a Centos linux box and there is interface connect to internet.
I stop the iptables in this box .
After a few day , I find the linux box have been hacked and install some perl script into the box .
Could anyone tell me how the hacker can login into the centos box without knowing the root passwd ???
How can they do it ?? please advise in detailed step...
Thank

作者: chuikingman   发布时间: 2014-07-10

What services was your CentOS running? Telnet? OpenSSH? ....
IF your root passwword was too simple, hackers could figure it out in no time!

作者: toylet   发布时间: 2014-07-10

use john?

作者: 星堤绝种   发布时间: 2014-07-10

john only for you has the password file
引用:原帖由 stone2549 於 2014-4-21 06:00 PM 发表
use john?

作者: stone2549   发布时间: 2014-07-10