Glaswegian

Spammers seem to be working a little bit harder these days, according to Symantec, which has reported that unsolicited email made up 90.4 percent of messages on corporate networks last month.

That represents a 5.1 percent increase over last month's numbers, but it's nothing out of the ordinary. For years, spam has made up somewhere between 80 percent and 95 percent of all email on the Internet.

Symantec reported that nearly 58 percent of spam is now coming from so-called botnets - networks of hacked computers that can be misused by criminals to steal financial information, launch attacks or send spam. The worst of the spamming botnets - called Donbot - generates 18.2 percent of all spam, according to Symantec.

These botnet computers can be rented out on the black market by anybody, but in recent months some spammers have been moving away from botnets, experimenting with a new way to sneak their unwanted email past corporate filters, according to Adam O'Donnell, a researcher with anti-spam vendor Cloudmark.

"Some of the larger ISPs are seeing a lot of non-bot-driven spam," O'Donnell said. With these campaigns, the spammer will rent legitimate network services, often in an Eastern European country such as Romania, and then blast a large amount of spam at a particular ISP's network. The idea is to push as many messages as possible onto the network before any kind of filtering software detects the incident.



http://www.techworld.com/security/ne...&NewsID=116437