Login attacks

[Gustavo Seabra]

Nathaniel Hall wrote:

> I see attempts about every other day.  Because of this, I send e-mails 
> to ISPs about every other day.  After the third offense from within 
> the same range, I block all access to our servers from that range, 
> unless the ISP attempts to correct the problem.
>
> I also keep track of all attempts so that I can reference it later in 
> case of a break in.
>
>Nathaniel Hall, GSEC
>Intrusion Detection and Firewall Technician
>Ozarks Technical Community College -- Office of Computer Networking
>
>halln at otc.edu
>417-447-7535
>  
>
>
>
> Gerry Doris wrote:
>
>>On Tue, 2004-12-07 at 15:24, Michael Yep wrote:
>>  
>>
>>>Hello
>>>
>>>In my LogWatch report I get many login attacks, many from the same IP address.
>>>
>>>sshd:
>>>    Authentication Failures:
>>>       root (218.232.109.187): 59 Time(s)
>>>       adm (218.232.109.187): 2 Time(s)
>>>       apache (218.232.109.187): 1 Time(s)
>>>       nobody (218.232.109.187): 1 Time(s)
>>>       operator (218.232.109.187): 1 Time(s)
>>>    Invalid Users:
>>>       Unknown Account: 43 Time(s)
>>>
>>>I have permitRootLogin set to NO, and I use strong passwords, but can I 
>>>just add these IP addresses to hosts.deny?
>>>and if so how would I set that up
>>>
>>>
>>>
>>>Michael Yep
>>>Development / Technical Operations
>>>RemoteLink, Inc.
>>>    
>>>
>>
>>I had so many problems with the 218.0.0.0/24 domain that I totally
>>blocked the entire domain.  I believe this domain is in Korea.
>>
>>  
>>
Hey guys,

I'm new to this security issues on Linux, but I find this thread 
interesting. Could some of you please point me to some docs where I can 
learn more (especially about these utilities and how to use them)?

Thanks,

-- 
------------------------------------------------------------------------
*Gustavo Seabra* 
<http://www.ksu.edu/chem/personnel/faculty/grad/jvo/ortiz/people_seabra.html> 
- Graduate Student
E-Mail: seabra at ksu.edu <mailto:seabra at ksu.edu>
Phone: (785) 532-6072 Chemistry Department <http://www.ksu.edu/chem/>
Kansas State University <http://www.ksu.edu>
Manhattan, KS 66506-3701