Hackers are going after organizations and businesses with a vengeance as detections of ransomware attacks are up 500% this year compared to this time last year.

The staggering increase in the number of detections stems from cybercriminals ramping up their efforts against organizations and businesses by preying on weak credentials, broad user access, and infrastructure holes, according to a new Malwarebytes Lab report. The report found the Troldesh ransomware – a type of malware that cybercriminals use to prevent users from being able to access their files or systems unless a ransom is paid – has been the biggest threat to organizations and businesses so far this year.

The report also listed the United States as the top country facing malware threats with 47% of detections, followed by Indonesia with 9% and Brazil with 8%.

The report comes after a string of recent ransomware attacks on U.S. cities and departments. Just this month, Georgia’s court system was shut down by a ransomware attack. Last month, Baltimore officials approved $10 million in emergency funding to recover from a ransomware attack after refusing to pay the $80,000 ransom demand.

Also last month, three Florida cities had their computer systems taken offline through ransomware attacks. The Village of Key Biscayne, located in South Florida, was the latest victim of an attack after Riviera Beach paid $600,000 and Lake City paid $460,000 in ransom demands to hackers to restore their data and computer operations.