LONDON – Computers manufactured by the world’s biggest personal computer maker, Lenovo, have been banned from the ?secret? and top secret – networks of the intelligence and defense services of Australia, the US, Britain, Canada, and New Zealand, because of concerns they are vulnerable to being hacked.

Multiple intelligence and defense sources in Britain and Australia confirmed there is a written ban on computers made by the Chinese company being used in ?classified? networks, CNET News.Com reported.

The ban was introduced in the mid-2000s after intensive laboratory testing of its equipment allegedly documented ?back-door? hardware and ?firmware? vulnerabilities in Lenovo chips. A Department of Defense spokesman confirmed Lenovo – products have never been accredited for Australia?s secret or top secret – networks.

The classified ban highlights concerns about security threats posed by ?malicious circuits? and insecure firmware in chips produced in China by companies with close government ties. Firmware is the interface be�tween a computer?s hardware and its operating system.

Lenovo, which is headquartered in Beijing, acquired IBM?s PC business in 2005.

IBM continues to sell servers and mainframes that are accredited for secret and top-secret networks. A Defense spokesman said Lenovo had never sought accreditation.

The Chinese Academy of Sciences, a government entity, owns 38 per cent of Legend Holdings, which in turn owns 34 per cent of Lenovo and is its largest shareholder.

Malicious modifications to – Lenovo?s circuitry.

AFR Weekend has been told British intelligence agencies? laboratories took a lead role in the research into Lenovo?s products.

Members of the British and – Australian defense and intelligence communities say that malicious modifications to – Lenovo?s circuitry ? beyond more typical vulnerabilities or ?zero-days? in its software ? were discovered that could allow people to remotely access devices without the users? knowledge. The alleged presence of these hardware ?back doors? remains highly classified.

In a statement, Lenovo said it was unaware of the ban. The company said its ?products have been found time and time again to be reliable and secure by our enterprise and public sector customers and we always �welcome their engagement to ensure we are meeting their security needs.?

Lenovo remains a significant supplier of computers for ?unclassified? government networks across western nations, including Australia and New Zealand?s defense departments.

A technology expert at the – Washington-based Brookings – In�stitution, Professor John Villasenor, said the globalization of the semi-conductor market has ?made it not only possible but inevitable that chips that have been intentionally and maliciously altered to contain hidden ?Trojan? circuitry will be inserted into the supply chain.

?These Trojan circuits can then be triggered months or years later to launch attacks,? he said.

Hardware back doors can be very hard to detect.

IT security industry analyst at tech research firm IBRS, James Turner, said hardware back doors are very hard to detect if well designed.

They were often created to look like a minor design or manufacturing fault, he said. To avoid detection, they are left latent until activated by a remote transmission.

?Most organizations do not have the resources to detect this style of infiltration. It takes a highly specialized laboratory to run a battery of tests to truly put hardware and �software through its paces,? Turner said. ?The fact that Lenovo kit is barred from classified networks is significant, and something the – private sector should look at closely.?

Professor Villasenor said malicious circuitry known as ?kill-switches? can be used to stop devices working and to establish back doors. French defense contractors reportedly installed kill-switches into chips that can be remotely tripped if their products fall into the wrong hands.

AFR Weekend has been told the electronic eavesdropping arms of the ?five eyes? western intelligence alliance, including the National Security Agency in the US, GCHQ in the UK, and the Defense Signals Directorate in Australia, have physically �connected parts of their secret and top secret computer networks to allow direct communications between them. This means that security bans on the use of products within the secret networks are �normally implemented across all five nations. Two commonly used suppliers are Dell and Hewlett-Packard.

The ban on Lenovo computers also applies to Britain?s domestic and foreign security services, MI5 and MI6, and their domestic equivalents: the Australian Security Intelligence Organization and the Australian Secret Intelligence �Service.

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