Security researcher Marcus Hutchins was sentenced to one year of supervised release by U.S. District Judge J.P. Stadtmueller for his role in creating the Kronos banking trojan.

Hutchins, a U.K. citizen, pleaded guilty in April for specific activity that took place between July 2014 and July 2015, which included marketing the Kronos banking trojan on the now-shuttered AlphaBay dark web marketplace.

Hutchins became a hero during the May 2017 WannaCry attacks when he triggered a kill-switch mechanism in the malware by registering an unclaimed domain that the ransomware was attempting to query. This effectively shut down the malware which had been hitting endpoints and organizations in more than 150 countries, spreading across networks using a wormable exploit.