Peter Williams, 39, admitted to selling eight pieces of critical software and information related to cybersecurity to a Russian broker in return for $US4 million ($5.6 million), which he used to buy jewellery, watches, homes and luxury holidays.

The tools were cyber-exploit components, meaning they can be used to identify weaknesses in technological systems, or to infect them with viruses.

faceless hooded hacker showing silence gesture. Hacker attack. Dangerous Hooded Hacker Breaks into Government Data Servers. Cybersecurity, computer hacker with hoodie. Hacking and malware concept.Williams sold components and information that could be used in cyber attacks. (Getty Images/iStockphoto)

These components could have given the buyer access to millions of digital devices within the US.

It is not known whether Russia or any other foreign government gained access to these materials and used them in a malicious way.

Williams was working as the general manager of Trenchant, an intelligence firm owned by US defence contractor L3Harris Technologies at the time of the thefts.

US defence contractor L3Harris Technologies. (Phelan M. Ebenhack/AP via CNN Newsource) (Phelan M. Ebenhack/AP via CNN)

The US Department of Justice claims Williams’ crimes cost his former employer $US35 million.

“Peter Williams stole a US defence contractor’s trade secrets about highly sensitive cyber capabilities and sold them to a broker whose clients include the Russian government, putting our national security and countless potential victims at risk,” FBI counterintelligence and espionage division assistant director Roman Rozhavsky said.

Williams had previously pleaded guilty to two counts of theft of trade secrets in October and entered a plea agreement with prosecutors to get a lighter sentence. The maximum penalty can be up to 10 years imprisonment.

As well as sentencing Williams to 87 months jail, US District Court Judge Loren AliKhan ordered him to forfeit $US1.3 million in cash, as well as cryptocurrency, properties, and other items purchased with the proceeds of the sales.

The Department of Justice accused Peter Williams of threatening the national security of the United States.The Department of Justice accused Williams of threatening the national security of the United States. (AP)

She claimed Williams’ offending impacted both the USA and Australia.

“Mr Williams acknowledges that his actions caused harm to the intelligence communities, both in the US and Australia,” she said.

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