Loanbase, the international Bitcoin crowd-lending platform known until recently as BitLendingClub, informed customers on Sunday that its systems had been breached.

According to a security notice sent out to customers, the attackers exploited a vulnerability in the company’s WordPress blog over the weekend and gained access to a database containing user information, including names, email addresses and phone numbers.

The hackers compromised at least four accounts that did not have two-factor authentication (2FA) enabled and stole roughly 8 BTC ($3,000). The company says the attackers have not accessed Bitcoin wallets and is confident that the maximum amount that may have been lost as a result of the attack is 20 BTC ($7,500).

Loanbase has promised to refund all users whose funds have been stolen in the breach.

The Loanbase website is currently offline, but the company expects to restore it on Monday morning. Once the site is back online, users will be asked to change their passwords and update their 2FA.

“We're going to implement additional security procedures, which will help with an earlier detection of such breaches,” Loanbase said.

Users have criticized the company for hosting WordPress, a platform that is known to be vulnerable to hacker attacks, on a server that is used for sensitive operations as well.

Companies that trade Bitcoin have been increasingly targeted by malicious actors. Last month, Bitcoin trader Cryptsy informed customers of a breach that took place in July 2014, arguing that it delayed the notification for so long because it had been unsuccessfully trying to get the FBI involved. The company said the attacker stole $5.7 million using an IRC backdoor.

The list of Bitcoin exchanges that reported suffering data breaches last year includes China-based Bter, Canadian firm CAVIRTEX, and Bitstamp.

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