US imposes sanctions on Uzbek national over alleged ties to Russian hackers

The Office of Foreign Assets Control under the US Department of the Treasury added Azizjon Mamasoev, born in 1987 and holding Uzbek citizenship, to its sanctions list. According to a press release published on the agency’s website, US authorities suspect him of connections with Russian cyber actors and involvement in offenses in the field of cybersecurity.

American officials disclosed his personal details, including passport information, as part of the designation.

In addition, a company affiliated with the Uzbek national – Advance Security Solutions, also referred to as Advanced Security Solutions – has been placed on the Specially Designated Nationals and Blocked Persons list. According to the Treasury Department, the firm was registered in Dubai, United Arab Emirates, in 2025. An address in Tashkent is also listed among its legal locations.

The company is said to operate in the field of offensive cybersecurity. Specifically, it allegedly acts as a broker for exploits, tools used to compromise computer systems, offering rewards for information about vulnerabilities in software developed in the United States.

Alongside the Uzbek citizen, several Russian nationals, Oleg Kucherov, Marina Vasanovich and Sergey Zelenyuk, were also sanctioned. Zelenyuk is suspected of organizing cyberattacks against US government agencies and medical institutions using malicious software. The Treasury Department stated that all of the designated individuals, including Mamasoev, provided material or technical support to Zelenyuk and his organization.

The Specially Designated Nationals and Blocked Persons list is the main sanctions register maintained by the US Department of the Treasury. Individuals and entities included on the list are subject to strict restrictions. Their assets under US jurisdiction are frozen, and US citizens and companies are prohibited from engaging in transactions with them.

In November 2025, the Office of Foreign Assets Control also added Datavice, a company registered in Uzbekistan, to its Russia related sanctions list. According to US authorities, the firm may have been involved in activities supporting Russian infrastructure or linked to cybercrime.