Israeli faces up to 20 years in US over $190M crypto hack - Ynetnews

Block, who holds both Israeli and Russian citizenship, was arrested on May 1, 2025, at Ben Gurion Airport in Tel Aviv. He had changed his surname from Gurevich to Block just two days prior and had received a new passport. His attempt to flee to Russia was thwarted by Israeli authorities.

The extradition request from the United States alleges that Block identified a security vulnerability in the Nomad platform in late July 2022. The platform allows users to transfer cryptocurrencies between different blockchain networks by locking up assets. Block allegedly altered the computer code responsible for verifying that assets had been locked, causing the system to issue him digital tokens without any corresponding deposit.

On August 1, 2022, Block withdrew approximately $2.8 million worth of tokens from Nomad's wallet. He subsequently converted the funds into various cryptocurrencies and transferred them between digital wallets to obscure their origin. This single act was part of a much larger breach that saw hundreds of users exploit the same vulnerability.

Copycat attacks and the aftermath

The Nomad hack was one of the largest and most chaotic in cryptocurrency history. After the initial exploit was discovered, news of it spread rapidly on social media. This prompted hundreds of users to replicate the attackers' actions, simply replacing the original wallet address with their own to withdraw funds without any specialized technical knowledge.

According to Nomad, more than 300 wallet addresses participated in the hack, which drained the platform of nearly all its assets. Research by Coinbase found that approximately 88% of the addresses involved belonged to 'copycats,' who collectively stole about $88 million. Two addresses associated with the original attackers withdrew most of the valuable tokens.

Following the breach, Nomad offered to let the hackers keep 10% of the stolen funds without facing prosecution if they returned the remaining 90%. Ultimately, about $36 million was returned. Block, however, contacted Nomad's chief technology officer under a false identity after the hack. He apologized, returned a small portion of the stolen funds, and demanded a $500,000 'reward' for discovering the vulnerability.

After Nomad offered him 10% of the stolen assets, he cut off contact. U.S. prosecutors filed an eight-count indictment against Block in 2023, including charges of computer fraud and money laundering. If convicted, he faces up to 20 years in prison, a substantially longer sentence than he would have faced under Israeli law.

Legal precedents and extradition

During the legal proceedings, an Israeli district court declared Block eligible for extradition. His appeal to the Supreme Court was rejected in a ruling that established significant legal precedents. The justices determined that the legal definition of 'unauthorized access to computer material' should be interpreted broadly enough to include the exploitation of security vulnerabilities and programming errors.

They also ruled that the public nature of blockchain networks does not preclude money laundering offenses. This is because the identities of wallet owners remain anonymous and the transfers make it difficult to trace the funds. Block's subsequent petition for a further hearing before the president of the Supreme Court was also rejected.

Attorney Avi Kronenberg of the International Affairs Department at the State Attorney's Office handled the extradition case. The extradition marks a significant step in the U.S. government's efforts to prosecute individuals involved in high-profile cryptocurrency hacks. Block is now expected to face trial in the United States.