US is top spammer

Security firm Sophos says that more than a fifth of the world's spam originated from the US in Q3 2006, reports PC World.

Sophos says that a possible reason for the US's increasing lead in relayed spam is the emergence of more than 300 strains of the mass-spammed Stratio worm. The worm, also known as Stration or Warezov, uses a trick dependent on the victim being able to speak English in its attempt to convert innocent PCs into members of a spam botnet.

After the US, which accounts for 21.6% of relayed spam in Sophos's list, comes China (13.4%), France (6.3%), South Korea (6.3%) and Spain (5.8%). The U.K. has successfully dropped out of the top 10 chart, and is in 13th position.

Hackers working for criminal gain are using increasingly sophisticated methods to ensure that the malware they develop is hard to detect and remove from infected systems, security researchers warned at this week's Computer Security Institute (CSI) trade show in Orlando.

The most popular of these approaches involve code mutation techniques designed to evade detection by signature-based malware blocking tools, code fragmentation that makes removal harder, and code concealment via rootkits.

Unlike mass-mailing worms such as MS Blaster and SQL Slammer, most of today's malware programs are being designed to stick around undetected for as long as possible on infected systems, said Matthew Williamson, principal researcher at Sana Security.

Sophos is warning home computer users about the potentially devastating consequences of using improperly secured computers, following news that a hacker who used computer malware to prey upon young schoolgirls has been jailed for 10 years.

Adrian Ringland, from the British town of Ilkeston, Derbyshire, admitted forcing schoolgirls to send him explicit pictures after he infected their computers with a spyware Trojan horse. The 36-year-old posed as a teenager in Internet chat rooms, in order to plant the malware onto girls' PCs. Victims believed they were opening a picture of their new online friend, but the attached file was really a Trojan horse that allowed Ringland to take over their computers. He then used stolen personal information and the ability to control their computers, to blackmail them into sending more and more explicit pictures.

"What's horrifying to realise is that it's only a matter of time before this happens again. These children will not be the last to be abused via the Internet using spyware," said Graham Cluley, senior technology consultant for Sophos.