A vast militia of infected computers is being marshaled, but how this botnet will be put to use remains unknown, reports Tim Greene at Network World.

Since August, malicious email attachments have been sent out in droves, potentially leaving millions of computers compromised, according to Commtouch, an Internet security company. After they've been infected, the machines can be remotely loaded with other malicious programs so that they can be used for sending out spam, launching DDoS attacks, stealing credentials from banks and breaching social media accounts. 

In the middle of August, there was a record spree of 25 billion malicious attachments sent with email on one day. Commtouch found that since then there have been five spikes in these malicious attachment campaigns. Each of the spikes reflects a scam used to trick recipients into clicking on the attachments. The first scam consisted mostly of fake notices from FedEx or UPS. Next came the "Map of Love" PDF, then a phony notice about a modified hotel room bill.

According to user forums, the scams were successful to some degree. However, Commtouch found that the botnet hasn't had an effect on spam volume so far because that traffic has been somewhat down. 

For more:
- see Tim Greene's article at Network World

Related Articles:
How an early warning system could protect against cyber attacks
Zeus Trojan mules used fake names, passports
Botnets won't be going away anytime soon