[asterisk-users] SIP authentication - Thoughts please

[Stefan Schmidt]

Am 07.10.10 10:52, schrieb Steve Davies:
> Hi,
> 
<snipped>

Hello,

i just want to say something about point 4 which comes to my mind about
security.

> 
> 4) I am not sure whether it is worth dropping through and testing auth
> against other peers if there is no username match. Can auth ever
> succeed under those circumstances (password matches, but not
> username?)

If you use UDP its very easy to fake the source ip of a call so do you
really want to open a door to an attacker by authenticate only by ip and
passwort which can match to any peer with the same ip adress? To
bruteforce this would be much easier than to bruteforce against sending
IP, right username and right password.

Have you tried to use different ports to register? i think this could help.


> Regards,
> Steve
> 
best regards

Stefan