The scale of the shut down is unprecedented.

The world’s most prolific source of spam emails has been shut down in a series of coordinated raids by Microsoft and US federal authorities.  The Rustock botnet, an international network of virus-infected computers, had for years generated billions of emails per day, promoting unlicensed online pharmacies and cut-price impotence pills.


But on Wednesday, security firms noticed email traffic from Rustock completely collapsed. 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 per cent effective,” said Richard Boscovich, senior attorney in Microsoft’s digital crimes unit, according to the Wall Street Journal.

The servers were rented from commercial internet hosting firms across the Mid West, who were apparently unaware of their role in Rustock. These “command and control” servers would issue instructions to infected home and business PCs worldwide.

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 emails.

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

“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.

Via Telegraph