[CentOS] How to tell if I've been hacked?

Wed Aug 19 03:58:08 UTC 2009
Christopher Chan <christopher.chan at bradbury.edu.hk>

Ryan Pugatch wrote:
> Christopher Chan wrote:
>   
>> Scott Ehrlich wrote:
>>     
>>> There is a lot of talk about the vulnerable Linux kernel.   I'm simply
>>> wondering the telltale signs if a given system has been hacked?
>>> What, specifically, does a person look for?
>>>   
>>>       
>> rpm -Va is a good start for modified binaries/libraries.
>> rootkit detectors is another thing you can try.
>>
>>
>> Other than that, it is checking your logs and looking for odd files 
>> lying around...
>>
>>     
>
>
> Also, processes running that you don't recognize.  Users you don't 
> recognize.  Logged in sessions that you don't recognize.  Free space 
> shrinking abnormally.  An increase in bandwidth usage that is unexpected.
>   

Yeah...one should not assume that those will be hidden by rogue 
libraries/binaries. Not every case will be taken that far or unspotted 
before it gets that far.