BLOCKCHAIN.INFO

DESCRIPTION OF EVENTS

"The world’s most popular crypto wallet. Over 80 million wallets created to buy, sell, and earn crypto." "As they say, not your keys, not your crypto. Blockchain.com Private Key Wallets are the most widely-used wallets for self-custody of your crypto. We make it easy for people who are ready to control their private keys to hold them with a Secret Private Key Recovery Phrase." "When it comes to ensuring that your crypto is secure, we think about every last detail so you don’t have to."

“[An] issue was present for a brief period of time between the hours of 12:00am and 2:30am GMT on December the 8th 2014. The issue was detected quickly and immediately resolved. In total, this issue affected less than 0.0002% of our user base and was limited to a few hundred addresses. We have sent an alert to all users who have potentially vulnerable addresses in their wallets, for which we have an email on file. We are committed to working with any affected users to assess and rectify any issues.”

"I only know about ~106 stolen coins, my assumption is that there must be much more that I don't know about."

"When making a scheduled software update overnight to our web-wallet, our development team inadvertently affected a part of our software that ensures private keys are generated in a strong and secure manner."

"We have sent an alert to all users who have potentially vulnerable addresses in their wallets, for which we have an email on file. We are committed to working with any affected users to assess and rectify any issues."

"If you created a wallet, generated a new address via Blockchain.info’s web-wallet, or sent bitcoin from your wallet during this time period and have not provided us with your email address, please contact our support desk at support@blockchain.zendesk.com or simply create a new wallet."

"This person claims to have been sweeping the affected addresses. He seems open to returning the funds. In my opinion he and blockchain.info should be put into contact as they could help get the coins back to where they belong. But you can contact him on that thread to attempt recovery as well."

"Affected users can contact the official portal for Blockchain user support. The company says that the support team is available seven days a week to help." "Our support team will respond to each individual case as quickly as they can. Some cases will require more research than others and this is to ensure the correct amount of funds are returned to each user who lost funds because of this issue."

Explore This Case Further On Our Wiki

The blockchain.info web wallet had a wallet generation exploit. Wallets were generated in a predictable way with a less secure R value for a few hours. This meant that the funds in those wallets could be snatched up by hackers. A combination of black and white hackers took funds. It would appear that blockchain.info made special effort to reimburse all affected users, though in at least one case a user reported their refund was sent to a hacker instead of them.

https://www.ccn.com/blockchain-reimbursing-stolen-bitcoins-users/ (Mar 26)
https://www.ccn.com/blockchain-info-security-update/ (May 18)
Blockchain.info Security Disclosure - Blockchain Blog (May 19)
Reused R values again (May 19)
Address: 1M77fUCzQrmY8jHRRgpzDVPAK5eQ31bwxZ | Blockchain Explorer (May 19)
Bitcoin price today, BTC live marketcap, chart, and info | CoinMarketCap (May 16)
Transaction: b72f8e5434a6af07eedcd30f72aa47afa21e1c3b447a94dc9a787412035fd75c | Blockchain Explorer (May 20)
At least hundreds of coins were stolen from Blockchain.info users last night, it's blockchain.info's fault, and no one is talking about it. : Bitcoin (May 20)
Reused R values again (Jul 9)
Reused R values again (Jul 9)

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