Bitfinex cryptocurrency exchange reports that it is investigating the recent hacker attack together with Canadian security systems developer Ledger Labs, though there is no sign of a breakthrough yet.

Ledger Labs is analysing Bitfinex security systems in order to accurately determine the mechanism of the attack and correct deficiencies in the system. The exchange addressed Ledger Labs within a few hours after the attack, Bitfinex reports. Apart from the investigation, Ledger Labs will perform a full audit of Bitfinex’ complete balance for both cryptocurrency and fiat assets and liabilities.

“The exact attack vector is as yet unknown, but Ledger Labs has already identified certain areas in our architecture that can be improved. Ledger Labs is working closely with our development and operations personnel to ensure that all of their recommendations are understood and fully implemented,” reads the statement.

Bitfinex informs that the exchange has currently suspended the use of BitGo cryptocurrency wallet and has returned to safe multi-signature cold storages with a minimal amount of coins left in its hot wallet.

“We are reassessing our storage options, both internally and with potential third party multi-sig vendors.”

Almost 120,000 bitcoins worth more than $60 mln were stolen from Bitfinex exchange as a result of a hacker attack on 2 August. After a few days of evaluation of the damage, the exchange decided to distribute the losses among all its customers. User account balances in all currencies have been charged 36.067%.

“We keenly feel the loss,” the company assures. According to the exchange, not only clients but also its managers and staff are subject to the loss distribution.

At the same time, Bitfinex acknowledged that part of the funds are reserved for the payment of auditor services, legal costs and other consulting services related to addressing the consequences the hacker attack.

Bitfinex statement that the mechanism of the hacker attack is still unknown caused an outcry among the members of bitcoin community. Some Reddit users reacted with sarcastic comments, noting that the Ledger Labs team includes Vitalik Buterin — Ethereum founder and designer, and one of the curators of The DAO, that lost over $50 mln due to a hacker attack in June.

“If anything this increases the causes for concern rather than alleviates them,” the user nicknamed logical wrote.

Many participants saw in the exchange’s statement an acknowledgement that in two weeks after the attack the company failed to find out any details of what had happened.

However, Bitfinex staff member Zane Tackett, who joined the thread, refuted such statements noting that “we did not say we don't have any information about the hack or no idea as you claim, we said the exact attack vector is unknown.”

The exchange customers also complain that their letters to Bitfinex with the request to clarify the particulars of the loss distribution scheme remain unanswered. In addition, the exchange has not given any details so far regarding the distribution of BFX tokens that will be used to set the losses on user accounts. These tokens will serve as debt notes for the exchange to restore lost assets to the clients in the future.

Elena Platonova