Might involve "downloading a software patch from a sanctioned organisation."
One of the Tornado Cash co-founders, Roman Semenov, said that his account was suspended at the GitHub development site as a result of the United States Treasury Department's approval of the privacy protocol.
Semenov claimed in a tweet on Monday that, although not being specifically listed as an SDN by the Treasury's Office of Foreign Asset Control, he appeared to be dealing with consequences because the Treasury claimed Tornado Cash had laundered more than $7 billion in cryptocurrency. Identified companies and people are designated as SDNs, and "U.S. persons are typically barred from interacting with them." Their assets are blocked.
Any contact made for business objectives, including associations on GitHub, would appear to fall under the definition of an SDN. The Federal Financial Institutions Examination Council and Office of Foreign Asset Control jointly stated that downloading a software patch from a sanctioned firm could be considered a prohibited transaction.
The decision to suspend his account was deemed "a little unreasonable" by Semenov. However, due to its alleged failure "to impose effective controls designed to stop it from laundering funds for malicious cyber actors on a regular basis and without basic measures to address its risks," according to Brian Nelson, Under Secretary of the Treasury for Terrorism and Financial Intelligence, Americans have effectively been prohibited from using the crypto mixer.
Some pro-crypto proponents have argued that the Treasury's actions against Tornado Cash were the sanctioning of a "neutral tool" as opposed to the targeting of people who were using it for illegal purposes. The U.S. Treasury Department's action, according to Jake Chervinsky, head of policy at the Blockchain Association, may have "crossed a line" between punishing criminal actors and those who undermine the tools and technology they might employ.
Tornado Cash is a cryptocurrency mixer that can be used to cover up transaction history for privacy concerns. In decentralised finance, the protocol was at the centre of various significant hacks and vulnerabilities, including as a $375 million attack on Wormhole in February and a $100 million hack on Horizon Bridge in June. After the Treasury Department claimed the North Korean hacking group Lazarus was responsible for a $600-million Ronin Bridge exploit, the company declared in April that it was using oracle contracts from Chainalysis to block wallet addresses that had been sanctioned by the Office of Foreign Assets Control.
