World's biggest source of spam e-mails shut down

ondon: The world's most prolific source of spam e-mails -- an international network of virus-infected computers -- has been shut down in a series of coordinated raids by Microsoft and US federal authorities. 

The Rustock botnet had for years generated billions of e-mails per day, promoting unlicensed online pharmacies and cut-price anti-impotence pills. A botnet is a collection of software agents that run autonomously and automatically. 

But early last week, security firms noticed that e-mail traffic from Rustock completely collapsed, the Telegraph reports. 

The scale of the shutdown is unprecedented. A report last month by SecureWorks, a computer security firm, said Rustock was the world's biggest source of spam. 

It has now been revealed that Microsoft, backed by US marshals acting on a court order, seized servers that it's estimated covertly controlled almost a million Windows PCs. 

"We think this has been 100 percent effective," said Richard Boscovich, senior attorney at Microsoft's digital crimes unit. 

The criminals behind the spamming business were named in Microsoft's lawsuit only as "John Does 1-11". 

To get the court order, which empowered it to seize equipment and so "decapitate" the botnet, Microsoft alleged the "John Does" infringed its trademarks in some of their e-mails. 

"The reasons for this are due to the author's relentless development of stealth tactics," it said, referring to how Rustock was frequently updated to stay one step ahead of anti-virus packages.