Re: What IP address is this log entry coming from? (Is "::" a valid IP address?)

[Jeff Trawick <trawick@xxxxxxxxx>]

On Thu, Sep 2, 2010 at 5:40 PM, J. Greenlees <lists@xxxxxxxxxxxxxxxxxxx> wrote:

Jeff Trawick wrote:
~snip~

%a is supposed to be an IP address, so what IP address is "::"? I'm only
somewhat familiar with IPv6 but I've never seen "::" before.

http://en.wikipedia.org/wiki/IPv6_address#Notation

One or any number of consecutive groups of zero value may be replaced
with two colons. [ ... ]

The localhost (loopback) address, 0:0:0:0:0:0:0:1, and the IPv6
unspecified address, 0:0:0:0:0:0:0:0, are reduced to ::1 and ::,
respectively.

and it is bogus to have the unspecified address as the client IP address

and if you check MS' RPC mechanism it uses 0.0.0.0 for the ip address to glom onto ANY available ip address. That suggests that the client giving the :: address is most likely a bot of some sort.
it could be a legitimate bot for an rpc mechanism, or it could be [ seems more likely ] to be one meant to find an exploitable weakness.

or, the client could be using an anonymizer  service before getting to the OPs site.

many reasons that it could be the ip unspecified address, only a few of which are cause for concern to the server admin.

That is the source IP address, which is required for routing replies (including those during the "connect" flow) back to the client, so I don't see how this can be 0 simply because of something the client is doing (other than triggering some sort of bug on the server side, of course).