[CentOS] Unknown rootkit causes compromised servers

Jim Perrin wrote:
> Along the lines of staying safe, now is probably a good time to check
> your password policies.
>
> 1. Don't allow root access to ssh. (modify /etc/ssh/sshd_config)
>   
why isn't this the default?

> 2. restrict root logins to only the local machine. (modify /etc/securetty)
> 3. Limit users with access to 'su' to the wheel group (use visudo and
> also modify /etc/pam.d/su)
>   
same question here.


> 4. Make sure root is the only one with a uid of 0. ( awk -F: '($3 ==
> "0") {print}' /etc/passwd )
> 5. Use pam to require strong passwords. (install/use pam_passwdqc
> which is part of the base distro, modify /etc/pam.d/system-auth )
> 6. Use denyhosts or pam.tally2 to restrict login attempts.
> 7. use ssh keys.
>   
[snip]