Re: [gentoo-user] Can't block pop3 attack

[kashani <kashani-list@badapple.net>]

Robin Atwood wrote:
> On Saturday 24 October 2009, Alan McKinnon wrote:
>> On Friday 23 October 2009 21:49:42 Robin Atwood wrote:
>>> My syslog is showing zillions of messages:
>>>
>>> Oct 24 02:25:58 opal xinetd[8054]: START: pop-3 pid=16534
>>>  from=61.134.64.199 Oct 24 02:25:59 opal xinetd[16534]: warning:
>>>  /etc/hosts.allow, line 7: can't verify hostname:
>>>  gethostbyname(199.64.134.61.broad.gs.dynamic.163data.com.cn) failed
>>> Oct 24 02:26:09 opal xinetd[8054]: EXIT: pop-3 status=0 pid=16534
>>> duration=11(sec)
>>>
>>> I run denyhosts but don't trap pop3 messages so I manually added the IP
>>> address to /etc/hosts.deny and..., it made absolutely no difference. I
>>> run qpopper which is compiled with xinetd support and xinetd uses tcpd,
>>> so I assumed the address would be blocked. Apparently not so. Any ideas?
>> You have allow ALL ALL early in hosts.allow, or
>> you have allow pop3 all earlier in hosts.allow
>  
> The second! I had forgotten about that. The trouble I set it up that way so I 
> could pick up email from arbitrary locations while travelling. It seems the 
> price of that is allowing idiots to spam your logs. 
> 
> Thanks for the pointer.
> -Robin

You might think about moving to pop3-ssl or imap-ssl and dropping the 
unencrypted protocols. Usually keeps people from banging on the servers 
and much safer if you use the occasional unsecured wireless network.

kashani