Binance fell victim to a successful hacker attack. Cybercriminals managed to withdraw 7000 BTC from the hot wallet of the exchange.

Binance users' fears were confirmed: unscheduled technical work, which was announced on 7 May with deposits and withdrawals suspended, was caused by a hacker attack.

“We have discovered a large scale security breach today, May 7, 2019 at 17:15:24 (UTC). Hackers were able to obtain a large number of user API keys, 2FA codes, and potentially other info. The hackers used a variety of techniques, including phishing, viruses and other attacks. We are still concluding all possible methods used. There may also be additional affected accounts that have not been identified yet. The hackers were able to withdraw 7000 BTC in this one transaction,” the exchange said in a statement.

Cybercriminals brought 7000 BTC (about $42 million) from the hot wallet of Binance. This accounts to approximately 2% of bitcoins held in cold storage of the cryptocurrency exchange.

Deposits and withdrawals of funds will remain suspended for one week.

"We must conduct a thorough security review. The security review will include all parts of our systems and data, which is large."

Trading operations are still available.

The exchange reported that the stolen funds will be reimbursed from its own assets from the #SAFU fund.

Binance recommended all users to change passwords and reset API keys. At 16.00 Moscow time, the old API keys were reset.

After Binance published its statement about the hacker attack, Changpeng Zhao, CEO of Binance, tweeted that the exchange team was considering the possibility of reorganizing the bitcoin network. In other words, Binance offered to activate a fork of the bitcoin blockchain in order to cancel hackers' transaction.

But this proposal was strongly criticized by the bitcoin community, which considers immutability as a fundamental advantage of decentralized currencies.

Popular bitcoin enthusiast WhalePanda commented on Zhao's proposal, saying that such anti-crisis measures are inappropriate in the bitcoin network:

Under a flurry of criticism, Zhao deleted his tweet about "reorg" and later wrote that the exchange abandoned this idea.