An international team of law enforcement officials has taken into custody a Chinese national and taken down a significant botnet that the man allegedly operated for almost ten years, making at least $99 million in profits by selling access to other criminals who used it for financial fraud, identity theft, and child exploitation, including schemes involving pandemic relief.
FBI Director Christopher Wray, as cited by the U.S. Department of Justice, stated on Wednesday that the “911 S5” botnet—a collection of machines in nearly 200 nations with malware on them—was perhaps the biggest in the world.
In a press release, Justice stated that Yunhe Wang, 35, was taken into custody on May 24. According to a LinkedIn post by Brett Leatherman, the FBI’s deputy assistant director for cyber operations, Wang was taken into custody in Singapore, and search warrants were carried out in both that country and Thailand. According to Leatherman, authorities also took $29 million worth of cryptocurrencies.
An indictment filed in the eastern district of Texas claims that since 2014, cybercriminals have stolen “billions of dollars from financial institutions, credit card issuers and accountholders, and federal lending programs” using Wang’s network of zombie household PCs.
In an announcement announcing the takedown, U.S. Attorney General Merrick Garland stated that Wang, the administrator, sold access to the 19 million Windows computers he had taken over—more than 613,000 in the US—to criminals. “They used that access to commit a staggering array of crimes that victimized children, threatened people’s safety, and defrauded financial institutions and federal lending programs.”
He added that over $5.9 billion in anticipated damages from fraud against humanitarian programs were caused by criminals who bought access to the zombie network from Wang. Authorities calculated that 560,000 false requests for jobless benefits came from hacked IP addresses.
Half of the 150 dedicated servers that Wang reportedly used to administer the botnet were rented from online service providers in the United States.
Wang allegedly acquired citizenship through investment in St. Kitts and Nevis, the United Arab Emirates, China, Singapore, Thailand, and the United States, among other countries, using the proceeds from his illegal activities, according to the indictment.
The Justice Department expressed gratitude for the support it received from police and other authorities in Singapore and Thailand in a press release.