[asterisk-users] Find a way to block brute force attacks.

[Gareth Blades]

Rodrigo Lang wrote:
> Hello list.
> 
> I'm trying to find a way to block any ip that tries to login more than 
> three times with the wrong password and try to log in three different 
> extensions. For I have suffered some brute force attacks on my asterisk 
> in the morning period.
> 
> The idea would be: Any ip with three attempts without success to log 
> into an extension is blocked.
> 
> Is there any way to accomplish this directly by the asterisk? Or is 
> there some kind of asterisk spit this information via the AMI?
> 
> I was wondering to make a Java program to listen to the AMI and create a 
> rule in iptables for ip in specific.
> 
> Does anyone have any suggestions?
> 
> 
> Thanks,
> Rodrigo Lang.
> 
Does asterisk log the failed attempts to a file?
If so then you could use sshblack to monitor the file for incorrect 
logins. It will add firewalls rules to a custom iptables chain based on 
various criteria. You can then point incoming SIP connections through 
this chain so offenders will be forewalled for a specific amount of time.
http://www.pettingers.org/code/sshblack.html