The US Treasury Department on Tuesday announced sanctions against three Chinese nationals accused of creating and operating a botnet named 911 S5.
The Treasury’s Office of Foreign Assets Control (OFAC) has designated Yunhe Wang, Jingping Liu, and Yanni Zheng, as well as Spicy Code Company Limited, Tulip Biz Pattaya Group Company Limited, and Lily Suites Company Limited, which are Thailand-based companies that are allegedly owned or controlled by Wang.
According to authorities, Wang was the primary administrator of 911 S5, while Liu was responsible for laundering criminal proceeds, mostly through cryptocurrency. Zheng is said to have acted as the power of attorney for Wang and one of his companies, making multiple payments and real estate purchases on his behalf.
911 S5 operated between at least 2015 and 2022, enabling cybercriminals to proxy their internet connection through compromised devices.
Its operators tricked many users into installing their software by offering ‘free’ VPN services. While the VPN service worked, the software also turned computers — without their owners’ knowledge — into proxies that could be used for illegal activities, such as payment card fraud. The service was also used to make bomb threats in the US.
“Once a cybercriminal had disguised their digital tracks through the 911 S5 botnet, their cybercrimes appeared to trace back to the victim’s computer instead of their own,” the Treasury said.
“The 911 S5 botnet compromised approximately 19 million IP addresses and facilitated the submission of tens of thousands of fraudulent applications related to the Coronavirus Aid, Relief, and Economic Security Act programs by its users, resulting in the loss of billions of dollars to the U.S. government,” it explained.
Cybersecurity blogger Brian Krebs had been monitoring the cybercrime operation and in 2022 he published the results of his research into the 911 S5 botnet. Shortly after Krebs published his blog post, which named Wang as the owner or manager of the service, 911 S5 was suddenly shut down, but reemerged a few months later as Cloud Router.
According to Krebs, Cloud Router now also appears to have ceased operations, just days before the Treasury announced the sanctions.
The sanctions come two months after the Treasury Department announced taking action against alleged Chinese hackers linked to the APT31 state-sponsored threat group.
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