A South Korean cryptocurrency exchange said it suffered a “cyberintrusion,” prompting bitcoin prices to fall sharply toward year lows.
Bitcoin dropped more than 10% over the weekend, falling below $6,700, according to research site CoinDesk. The largest cryptocurrency has lost more than half its value this year, falling by nearly two thirds from its record high near $20,000 in December. Its low for the year came in February at less than $6,000.
Other large cryptocurrencies like Ethereum, ripple and bitcoin cash have all fallen more than 11% over the past 24 hours. EOS, the token backed by startup block.one which has raised more than $4 billion, is down 20%, according to research site coinmarketcap.com.
The latest declines came after a small exchange called Coinrail said Sunday several so-called alt coins—alternative versions of bitcoin—appeared to have been stolen in the attack. Coinrail said 70% of its digital assets have been moved to what is known as a cold wallet—storage that isn’t connected to the internet—and that it is working with authorities on finding the lost assets.
Coinrail didn’t say how much was stolen in terms of value, but it is possible that more than $40 million worth of alt coins were taken, according to a wallet address that some have said belongs to an attacker.
South Korea is a hotbed for cryptocurrency trading. But Coinrail is small relative to its competitors. Before the attack, Coinrail ranked near the bottom of the 100 biggest cryptocurrency exchanges in the world by trading volume, according to data from coinmarketcap.com.
South Korean regulators have taken a tough stance in trying to tame the cryptocurrency market, which is one of the world’s most busiest as measured by trading volume. Exchanges in South Korea have a history of being hit by cyberattacks.
Hacking has been a problem for the cryptocurrency market world-wide in recent years. In January, Japanese exchange Coincheck Inc. was attacked and a small Italian exchange called BitGrail was hit in February. Since 2014, exchange hacks have cost investors at least $1.4 billion, according to an analysis by The Wall Street Journal.
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