The National Security Agency (NSA) has infected more than 50,000 computer networks worldwide with data-stealing malware according to documents from NSA whistleblower Edward Snowden.

“The malware can be controlled remotely and be turned on and off at will,” according to the NRC Handelsblad report.
“The ‘implants' act as digital ‘sleeper cells' that can be activated with a single push of a button.”
Some of the malware was said to remain undetected on networks for 22 years. The NSA attacks were reportedly carried out by a special department known as Tailored Access Operations, which was said to employ more than a thousand hackers.