[CentOS] Unknown rootkit causes compromised servers

Les Mikesell lesmikesell at gmail.com
Tue Jan 29 04:07:13 UTC 2008


Jim Perrin wrote:
> On Jan 28, 2008 10:14 PM, Les Mikesell <lesmikesell at gmail.com> wrote:
>> Craig White wrote:
>>>> We will work also with the Red Hat Security team and see if we can
>>>> isolate any issues that might be FIXABLE.
>>> ----
>>> doesn't this almost beg for upstream to make denyhosts a base install
>>> and automatically on, just as sshd is automatically on?
>> I've always wondered why a program like sshd didn't rate-limit
>> connection attempts from day one.  It's not exactly a new concept,
>> especially for a security-oriented program.
> 
> It's a question of scale. For some systems, 30 people logging in is
> too many. For others, it's 3000. There is no 'right' default value. It
> should be (and is) left up to the admin and iptables.

You have to have some default and it might as well be on the secure side 
  since as you suggest you won't be right for everyone.  But, you don't 
have to rate-limit connections in general, you just need a delay after a 
failed attempt before permitting another attempt from the same place.  I 
thought getty/login always had such a delay to discourage password 
guessing so it seemed odd for ssh to ignore this risk.

-- 
   Les Mikesell
    lesmikesell at gmail.com




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