HONG KONG — Nearly 120,000 units of digital currency bitcoin worth about US$72 million was stolen from the exchange platform Bitfinex in Hong Kong, rattling the global bitcoin community in the second-biggest security breach ever of such an exchange.Bitfinex is the world’s largest dollar-based exchange for bitcoin, and is known in the digital currency community for having deep liquidity in the U.S.Zane Tackett, Director of Community & Product Development for Bitfinex, told Reuters on Wednesday that 119,756 bitcoin had been stolen from users’ accounts and that the exchange had not yet decided how to address customer losses.“The bitcoin was stolen from users’ segregated wallets,” he said.The company said it had reported the theft to law enforcement and was cooperating with top blockchain analytic companies to track the stolen coins.Last year, Bitfinex announced a tie-up with Palo Alto-based BitGo, which uses multiple-signature security to store user deposits online, allowing for faster withdrawals.

“Our investigation has found no evidence of a breach to any BitGo servers,” BitGo said in a Tweet.“With users’ funds secured using multi-signature technology in partnership with BitGo, a lot more is at stake for the backbone of the bitcoin industry, with its stalwarts and prided tech under fire,” said Charles Hayter, chief executive and founder of digital currency website CryptoCompare.The security breach comes two months after Bitfinex was ordered to pay a $75,000 fine by the U.S.Commodity and Futures Trading Commission in part for offering illegal off-exchange financed commodity transactions in bitcoin and other digital currencies.Tuesday’s breach triggered a slump in bitcoin prices and was reminiscent of events that led to the 2014 collapse of Tokyo-based exchange Mt Gox, which said it had lost about US$500 million worth of customers’ Bitcoins in a hacking attack.Bitcoin plunged just over 23 per cent on Tuesday after the news broke.On Wednesday it was up one per cent at US$545.20 on the BitStamp platform.

Tackett added that the breach did not “expose any weaknesses in the security of a blockchain,” the technology that generates and processes bitcoin, a web-based “cryptocurrency” that can move across the globe anonymously without the need for a central authority.A bitcoin expert said the scandal highlighted the risks of companies using cryptography for their ledgers.“The more you rely on its benefits, the greater the potential for damage when keys are stolen.We still have some way to go to create highly secure but convenient systems,” said Singapore-based Antony Lewis.The volume of bitcoin stolen amounts to about 0.75 per cent of all bitcoin in circulation.It is not yet clear whether the theft was an inside job or whether hackers were able to gain access to the system externally.On an online forum, Bitfinex’s Tackett said he was “nearly 100 per cent certain” it was no one in the company.Bitfinex suspended trading on Tuesday after it discovered the breach.It said on its website that it was investigating and cooperating with the authorities.

The security breach is the latest scandal to hit Hong Kong’s bitcoin market after MyCoin became embroiled in a scam last year that media estimated could have duped investors of up to US$387 million.The bitcoin trading company closed after the scandal.The president of the Hong Kong Bitcoin Association said the only way to protect information is to disperse it in so many small pieces that the reward for hacking is too small.cours prix bitcoin“For an attacker, the cost-benefit strategy is quite easy: How much is in the pot and how likely is it that I’m getting the pot?” said Leonhard Weese.bitcoin zdarmaJump to: , A hardware wallet is a special type of bitcoin wallet which stores the user's private keys in a secure hardware device.sell bitcoin with skrill

They have major advantages over standard software wallets: This page is an attempt to summarize all the known developments of hardware wallets that can use Bitcoin as part of their operation.Contents 1 2 3 4 5 6 To date there have been no verifiable incidents of Bitcoins stolen from hardware wallets.ethereum nxtHardware wallets are relatively new, but at least for the time being they have maintained a good track record, unlike the numerous incidents of Bitcoin theft from Internet-connected computers.can i get my bitcoins back from silkroadHowever, it's important to understand that hardware wallets are a high value target and depend on various assumptions holding true to maintain security.most valuable bitcoin domains

They are not a silver bullet, and there are several realistic ways in which a hardware wallet can fail to protect your Bitcoin.These risks need to be carefully considered when deciding how much trust to place in a hardware wallet, and which hardware wallet to buy.How a hardware wallet could fail to protect your Bitcoin: The Pi-Wallet is a small computer with the Armory bitcoin client.Transactions are signed offline, then transferred on a USB stick via Sneakernet to an online system for broadcasting.Confirming the transaction with TREZOR TREZOR is a secure bitcoin storage and a transaction signing tool.The private keys are generated by the device and never leave it thus they cannot be accessed by a malware.It uses a deterministic wallet structure which means it can hold an unlimited number of keys (BIP 0032/BIP 0044).A recovery seed is generated when the device is initialized.In case TREZOR gets lost or stolen, all its contents can be recovered using this seed (private keys, bitcoin balance and transaction history) into a new device or another BIP 0039/BIP 0044 compatible wallet.

TREZOR also introduced a unique way of PIN entering preventing keyloggers from recording it even when entered on a compromised computer.An encryption passphrase can be set on top of the PIN protection.More passphrases can be used for plausible deniability. | HW.1 inserted in a laptop HW.1 is an implementation of a deterministic (BIP 0032) Hardware Wallet on a USB smartcard.It is typically used as a blind secure device for multi signature transactions - holding a set of derived private keys and signing transactions without requiring user confirmation.Power users can rely on it to confirm all transactions with a second factor scheme turning the dongle into a keyboard typing what the user is supposed to have signed, as a protection against malware.It is also possible to customize HW.1 for more specific needs, such as creating a prepaid card without revealing the deterministic seed before it is received by the user, or securing bitcoin transactions on a server.Ledger Nano protects your Bitcoin data within a smartcard.

Its micro-processor certified against all types of attacks (both physical and logical), and has been used in the banking industry for decades (think credit card chips).The device connects to your computer through the USB port and will do all the Bitcoin cryptographic heavy lifting such as signing transactions inside its secure environment.You can therefore use your Bitcoin account with maximum trust, even on an insecure or compromised computer.The second factor verification of the transaction signature can be done either with a paired smartphone (Android, iOS) or a physical security card.The Ledger Wallet Chrome application (available also on Chromium) provides an easy onboarding as well as a seamless user experience, and the Nano is compatible with numerous third party software: Electrum, Mycelium, GreenAddress, Greenbits, Coinkite and Copay.Ledger Nano product page | Source and specifications The Ledger Unplugged is a credit card sized NFC hardware wallet.It embeds an open source Java Card app and is compatible with all NFC enabled Android phones.

The device can be used with Mycelium or Greenbits.In case of loss, you can restore it on any Ledger Wallet (Nano or another one) or all other compatible solutions (BIP 39).Ledger Unplugged product page | Source code Chinese clone of Trezor BWALLET is a clone of Trezor by a Chinese company.Trezor code is open source and this device operates like a Trezor. website and it does not work with Trezor official firmware.KeepKey showing a bitcoin transaction that needs to be manually approved.KeepKey is a USB device that stores and secures your bitcoins.When you entrust KeepKey with your money, each and every bitcoin transaction you make must be reviewed and approved via it's OLED display and confirmation button.KeepKey has a unique recovery feature utilizing a rotating cipher to restore private keys with a BIP 0039 recovery seed.This means it is not necessary to store your private keys on KeepKey: the recovery process is secure enough so that KeepKey can be used as a transaction device for paper wallets.

The 1st Bitcoin Bearer Bond or just call it a "Bitcoin Stick" Opendime is a small USB stick that allows you to spend Bitcoin like a dollar bill.Pass it along multiple times.Connect to any USB to check balance.Unseal anytime to spend online.It comes in the shape of a mini USB, and setting it up is astonishingly quick and simple.You plug OpenDime into a USB port, and it behaves just like a USB drive with a tiny amount of storage.In its folder, is a web page.You open the webpage in your browser, and there’s only one instruction to follow: “Drop a file onto the drive”.Once you do that, the OpenDime automagically generates a unique address for you to receive Bitcoin with.CoolWallet showing Launch App, waiting for user to connect with smartphone via Bluetooth CoolWallet is a credit card sized Bluetooth device that stores and secures your bitcoins and private keys.It fits in your wallet and works wirelessly.Every Bitcoin transaction must be manually confirmed and approved through its e-paper display and button.

CoolWallet only acknowledges the paired smartphone.Whoever stole the CoolWallet are not able to steal any bitcoins.Using recovery Seed can restore all your bitcoins in case you lost the device. | Source and specifications Graphic printed on front of BlochsTech cards.The BlochsTech open Bitcoin card is an open protocol secure hardware Bitcoin wallet your grandmother could use.For shops it's faster to accept than slow QR code based wallets and more reliable as it works offline.Currently it's of course in a novelty phase like Casascius coins (of which thousands were sold), however in the long run it is fully capable of functionally replacing the VISA system in all nations.BitLox Bitcoin Hardware Wallet BitLox is a metal cased (aluminum or titanium) bitcoin hardware wallet that works with their own web based wallet by USB and apps for iPhone and Android using Bluetooth LE.At present it is the only bitcoin hardware wallet you can buy that works with iPhone.The device weighs one ounce and is the size of a credit card 4 mm thick.

Bitlox allows you to set up hidden wallets.Unlike other hardware wallets your seed is never displayed on a connected computer or phone but only on the Bitlox.All your wallet, device and transaction PINs are only entered on the BitLox and never on any app.BitLox has also implemented several advanced security features not available on any other bitcoin hardware wallet.Digital Bitbox Hardware Wallet Ledger Wallet Nano S Ledger Nano S is a secure Bitcoin hardware wallet.It connects to any computer through USB and embeds a built-in OLED display to double-check and confirm each transaction with a single tap on its buttons.It is architectured around a Secure Element (ST31 family) and built on top of the BOLOS platform, a powerful and flexible Operating System allowing the secure execution of multiple Open Source applications in full isolation.Ledger Nano S product page Incorporates a e-paper display, keypad, and radio (custom ISM band protocol.)Unfortunately it is fairly limited in terms of transaction I/O, requiring a radio gateway or another bitcoincard wherever funds need to be transferred.