Coinbase continues to face fallout from a recent security breach after the hacker behind the attack sent a public taunt to blockchain investigator ZachXBT. The message was posted Wednesday evening using Ethereum transaction data, as the attacker moved tens of millions of dollars in stolen assets across blockchain networks.
The incident occurred ten days after Coinbase disclosed that over 69,000 customer accounts had been compromised in a December 2024 cyberattack. The mocking message on the Ethereum blockchain adds a new twist to the high-profile case.
Ethereum message targets on-chain investigator
The hacker used a blockchain transaction to send a brief insult to ZachXBT, writing “L bozo” in the input data field. The message also included a link to a YouTube meme video featuring NBA Hall of Famer James Worthy smoking a cigar, apparently intended to mock the crypto investigator.
ZachXBT shared the interaction through his Telegram channel “Investigations” and linked the sender to the same actor responsible for the Coinbase hack. The attacker has reportedly used on-chain messages before to communicate or provoke those tracking them.
Coinbase hack and crypto laundering activity
Coinbase confirmed on May 21 that the data breach had impacted 69,461 users and stolen customer information. The company discovered the breach earlier, on May 11, and disclosed it in a filing with the Maine Attorney General’s office.
According to ZachXBT, the attacker behind the taunt also demanded a $20 million Bitcoin ransom shortly after the incident became public. Coinbase declined to pay and offered the same amount as a bounty for leads on the hacker’s identity.
On Tuesday, the hacker began liquidating some of the stolen funds. Blockchain records show that 17,800 ETH were converted into $44.94 million worth of DAI through THORChain. The swaps were made at an average rate of $2,528 per ETH, including a transaction converting 9,080 ETH into $22.82 million in DAI.
Coinbase faces security and market pressure
The breach has damaged Coinbase’s reputation as it prepares for broader institutional exposure. Due to remediation and customer compensation, the company’s estimated financial impact ranges from $180 million to $400 million.
Coinbase (COIN) Shares closed at $258.97 on Wednesday, down 0.92 percent. The stock has declined over 36 percent in the past month.
Meanwhile, Binance and Kraken also faced social engineering threats, which were successfully blocked. Both exchanges confirmed that no customer data was exposed in those attempts.