The Russian Federal Security Service (FSB) suffered the biggest data leak in its history after a hacking group operating under the name 0v1ru$ recently obtained unauthorized access to the network of Sytech, a contractor for the FSB.

After stealing 7.5TB of data from Sytech, 0v1ru$ shared the information with a second hacking group, called DigitalRevolution, which then leaked the information to the Russian media. BBC Russia reports that the data includes information on a number of secret projects Sytech was developing for the FSB. For instance, Sytech was working on a project aiming to de-anonymize users on the Tor network.

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