Reports: Russian hackers stole classified US cyber tools from NSA
The details, first reported by the Wall Street Journal, will likely be considered the most significant US security breaches in history.
The theft reportedly included tools to infiltrate foreign computer networks and protect against cyber-attacks.
Reports: Russian hackers stole NSA's cyber secrets
Hackers infiltrated NSA contractor's PC through Kaspersky anti-virus software
The NSA contractor worked at the agency's Tailored Access Operations unit for elite hackers before being fired in 2015, the Washington Post later reported.
A former senior intelligence official said the contractor placed the classified information on a home computer that used the Russian-origin Kaspersky anti-virus software, according to NBC News.
The Russian hackers used Kaspersky to identify and access the computer.
Hacking reports come amid simmering US-Russia tensions
The revelations come as tensions simmer between the US and Russia. US intelligence agencies have accused Russian hackers of targeting American state election agencies and hacking the computers belonging to the Democratic Party to help Donald Trump win the 2016 Presidential election.
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Latest in a series of data breaches to hit NSA
If confirmed, the revelations are the latest in a series of hacks to hit the NSA, which include the 2013 leaks by former contractor Edward Snowden.
"The NSA needs to get its head out of the sand and solve its contractor problem," said Republican US Senator Ben Sasse, who called the reports, if true, alarming.
The NSA has declined to comment on the reports.
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