Some IT administrators are returning to work after the long holiday weekend in the U.S. to a shock, as what may be the largest-ever cyberattack continues to rip through computer systems around the world.

An estimated 1,500 businesses have had their data held for ransom by a gang of cybercriminals known as REvil. The hackers apparently exploited a weakness in the software company called Kaseya.

Here & Now‘s Jane Clayson speaks with Delaram Kahrobaei, chair of cybersecurity in the Department of Computer Science at the University of York.

This article was originally published on WBUR.org.

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