When downloaded, the tainted versions of the report allowed hackers to remotely control infected computers.
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The botnet also had the ability to use the infected computers to "recruit" other machines into the network.
BBC: '$1m-a-year' botnet shut down by Microsoft and Symantec
Several versions instructed infected computers across myriad time zones to download a Trojan at the same single, synchronized moment.
He added that the company was able to spot the botnet thanks to a very specific behaviour of the infected computers.
In 2002 they were flooded with traffic from tens of thousands of infected computers in an unsolved "distributed denial of service" attack.
The first version of Sobig prompted infected computers to download Trojans that had been invisibly parked at Geocities, Yahoo's free Web-hosting service.
That data can then be amplified by 1, 000 or if those original enquiries are made through a botnet, or network of infected computers.
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The other virus -- backdoor.breut -- sends the information it pillages from infected computers to the IP address: 216.6.0.28 and does not hide this.
Until now, Storm's creators have been focused on growing its ranks: Infected computers have sent out spam, drawing users to compromised Web sites that hijack more PCs.
The court heard the other two viruses had real destructive qualities and were programmed to stop computers operating and when infected computers were re-booted, the viruses would destroy material.
The worm that infected computers at the Marine Corps headquarters at the Pentagon early Friday was ExploreZip, an especially malicious virus that typically travels by e-mail, according to a Marine Corps spokesman.
Twitter said the site's blackout was caused by a "denial-of-service attack, " which likely means a hacker used a number of infected computers to send enough automated requests to the site to overwhelm it.
Internet security firm FireEye has spotted some 450, 000 infected computers from the Srizbi botnet - alleged to account for as much as half of all the spam on Earth - trying to "phone home" and reach their command and control servers.
In October of last year, the company was duped into running a series of fake advertisements laced with malware that infected the computers of many readers.
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Dozens of Syrian activists have alleged pro-regime hackers have infected their computers with spyware and viruses designed to monitor their activities and collect information about their sources.
The firms said computers infected by the Bamital botnet were being used for identify theft.
BBC: '$1m-a-year' botnet shut down by Microsoft and Symantec
Over the past year, the number of PCs ensnared in botnets--herds of users' computers infected with malicious software--has more than quadrupled, according to botnet researchers at the Shadowserver Foundation.
Mr Bendelladj, who used the alias Bx1 online, is believed to be one of the "critical" controllers of the SpyEye software that infected users' computers and then stole personal information used to log in to online financial accounts.
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It estimates that up to 11, 000 personal computers were infected by malware and recruited for the attack.
The officials said more than a million computers were infected across Great Britain, France, Germany, Italy, Poland, Finland and Turkey.
Symantec estimates that the number of computers still infected is down to about 270, 000, slightly less than half of the number that was reported a week ago.
Its Digital Crimes Unit carried out the operation to tackle the bonnet, which is estimated to have infected approximately one million computers and is capable of sending billions of spam mail every day.
The New York Times (registration required) takes a deeper look at what happens to computers that get infected by malicious code and taken over.
According to FBI files acquired by The Smoking Gun, the bot infected over half a million computers and could sent ten billion pieces of spam per day.
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Washington (CNN) -- Federal authorities Wednesday announced an indictment charging three men in connection with a massive international cybercrime scheme that involved creating and distributing a virus that infected more than a million computers in the U.S. and Europe.
Connect those data firehoses to computers that have been infected with malicious software that turns them into criminally-controlled botnets, and you can expect them to spew out more malicious traffic than ever.
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Investigators from Europol's European Cybercrime Centre - which launched last month - said the network had infected "tens of thousands" of computers worldwide.
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The Foreign Secretary William Hague revealed in February that computers belonging to the government had been infected with the "Zeus" computer virus, after users opened an e-mail purporting to come from the White House and followed a link.
Last week, a Russian security company reported that as many as 600, 000 Macs, most of them in the United States and Canada, had been infected by Flashback, a Trojan horse virus that infiltrates computers, secretly giving someone else remote access to them.
The ongoing US government investigation alleges that the scheme began in Europe and later spread to the US, where at one stage more than 190 computers belonging to America's Nasa space agency were infected.
BBC: Europeans charged in US over destructive computer virus
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