Bots use in CyberCrime increasing

As mentioned while looking at spam filtering in previous blogs, botnets
(networks of ‘bots’) are being noted as an increasing source of
cyber-criminal activity. A securityfocus article
(http://www.securityfocus.com/brief/195?ref=rss) quotes shocking figures
from The Messaging Anti-Abuse Working Group; as many as 7% of PC’s
worldwide are infected and working as active bots, that’s around 47
million. They also estimate that bots now send 70% of all spam–this is
an increasing problem for System Administrators as it means many more
residential broadband IP addresses are being blacklisted by projects
like SpamHaus. I have had several instances where users trying to send
mail from outside of the corporate network have been unable to due to
being in a dns blacklist (while not infected themselves, a previous user
of the dynamic IP address must have been).