Botnet database, overzealous?

[Robert Zeff]

                   We set up botnet filtering yesteray.  We have about 300 users behind the ASA-5510.  What a great tool!  But, the filter claims that we have about 70 "infected machines".

I investigated some of the IPs, like 173.194.79.99.  That IP belongs to Google and if you try http on that IP you get their search engine.  And every hit that we got was said to be "very high risk".  Many of the IPs that are in the database appear to innoculous.  So I'm wondering what's going on.

Also, we use DNS substitution.  When I enable DNS snooping, the substitution doesn't work, the query returns th outside IP.  I hava a SR open on this.

Interested in comments,

-

RObert

[scchesney]

I set up the same thing last Thursday, and am seeing the same thing - connections to Google.com at

173.194.79.99 is logged as a malware site with a threat level of 'very-high'.

It's hard to appear credible to management if we're calling google a high threat.

--Scott

[Robert Zeff]

We did a bit of sniffing and found tha the "infected" hosts we not actually infected,  Most often the user was visiting a compromised ecommerse site (usually built with an outdated version of Wordpress) and these site were redirecting to a malware site.  So the cases that we looked at, the user was not infected (yet)

It is dropping about 1000 connections across 40 PCs per day.

We have enabled automatic blacklisting and have not yet had any complaints.

-Robert