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The Australian government has launched the Cyber Security Awareness Week.

Just after hacker collective LulzSec threw in the towel, granting internet users a brief interlude of peace of mind, a new malicious botnet has been discovered.

Discovered by security researchers at Kaspersky Labs, the new botnet is called TDL-4. It is estimated to have already infected as many as 4.5 million computers.

The TDL-4 botnet virus is reportedly distributed via rogue websites offering pirated content or file storage.

Botnets are a common tool of organised crime. A botnet is made when a virus infects a number of computers to create its own network. The network allows those behind it to remotely control the infected computers.

Website operators hosting the TDL-4 virus and botnet are reportedly paid between $20 to $200 by the criminals behind it. The exact amount is based on how many machines they manage to infect.

The estimated 4.5 million figure is apparently a conservative guess, with Kaspersky Labs indicating that its research numbers only refer to the first three months of this year -- meaning that far more computers could already be infected.

The research clarified that nearly a third of all computers infected with the virus were in the United States, while only a twentieth were in Britain.

The TDL-4 virus has caused particular concern thanks to its "sophisticated" nature. The virus apparently uses a series of complicated techniques to bypass even the most cutting-edge anti-virus software. It also eliminates its competition by targeting and deleting any other viruses it encounters.

The strong encryption used in the virus also reportedly makes it close to impossible for authorities to track its origin point. Though, the fact that the virus has not targeted any of Russia's internet users has led to speculation that it may be a Russian criminal organisation behind the new cyber threat.

The botnet's peer to peer nature has also caused significant concern, earning TDL-4 the title of "indestructible". In its report Kaspersky Labs highlighted that even if authorities managed to track the virus and seize control of its servers, the virus peer to peer configuration would mean that the criminals behind it would still be in command.

Peer to peer networks function by distributing the network's application architecture that partitions tasks or workloads between multiple peers -- computers. This means that unless the network as a whole is shutdown, the virus will continue to function unfazed.

The news comes just after a similar Trojan virus was reported by internet provider Virgin Media last month.