North American Network Operators Group
Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical

Re: snmp vuln

  • From: Saku Ytti
  • Date: Thu Apr 22 03:22:30 2004 
On (2004-04-21 23:24 -0700), Alexei Roudnev wrote:

> If you ever read SNMP specs, you can realize, that there is not any C or C++
> SNMP  implementation without such problem. So, rule number 1 is _never
> expose SNMP to Internet, and be careful to filter out any inbound packets,
> forwarded to your SNMP ports.

 Which makes me wonder, why in most implementations services listen in
each configured address. Provider might have lot of link networks, even
from customers demand from his link network. This makes filtering in 
borders little less feasible. And for this particular attack two
way comminication is not needed, so SNMP with ACL is not enought to
mitigate this. With explicitly defined listen addresses, filtering in border
would be easy.
 JunOS allows to set interfaces to SNMP, but according to netstat it
still listens in *.161.

-- 
  ++ytti