The fiat-crypto exchange Coinmama have been hacked, they said in an official post, as roughly 450,000 email-password pairs have been found for sale on the dark web. Critically, the hacked credentials are not from recent accounts – only accounts made prior to 5 August, 2017 have been stolen.

The stolen Coinmama credentials are part of a far larger booty. ZDNet reported on February 14 that a total of 747 million credentials grifted from 24 total entities were up for sale, of which the Coinmama tranche is a tiny fraction.

The entire collection was for sale on the “Dream Market” dark web market for about $15,000. But ZDNet also reported the collection is no longer for sale on the open market, because of buyers’ complaints that the public sale would – ironically – lead to leaks of the stolen goods. Some websites, like Haveibeenpwned.com, index stolen credentials so that users can check if their own credentials are compromised and known to identity thieves.

Coinmama are on guard for “any external indication that the compromised data is being used,” and encourage users with potentially affected accounts to change their passwords as soon as possible.

There was no mention of whether Coinmama users’ personal details were also leaked, in addition to username/password pairs. The exchange requires an extensive amount of Know-Your-Customer/Anti-Money-Laundering information to be submitted, in order to take full advantage of the service, including multiple IDs and even utility bills.

Dark Web Sales

CryptoGlobe recently reported that $600 million worth of bitcoin was used for dark web transactions during 2018, an amount only slightly down since the previous year. An economist at Chainalysis, a blockchain security analytics firm, speculated that increased law enforcement on dark web markets may account for the drop.

Another collection of stolen credentials of similar size was recently put up for sale on the dark web. But there is no immediate indication that the sales are in fact the same collection.