Bitcoin Paper Wallet ‘Back Door’ Responsible for Millions in Missing Funds.

[Malam90]

BitcoinPaperWallet.com appears to feature a back door in its code that shares private keys for its paper wallets with anyone who has access to the website’s backend.
CoinDesk has spoken to BitcoinPaperWallet users who collectively claim to have lost millions of dollars worth of bitcoin.
Blockchain analysis shows these funds flowing to Binance and Poloniex exchanges.
The unfortunate scenario is a reminder that, in most cases, web-based bitcoin wallet generators should be avoided in favor of vetted bitcoin wallet software and hardware.
It was just past midnight on Jan. 7, 2021, when “Nick Wendell” (a pseudonym) lost half a million dollars in bitcoin.

Bitcoin’s price was roaring toward $40,000, and Wendell was moving some of his bitcoin to a paper wallet generated by BitcoinPaperWallet.com. These wallets allow you to store your private key on a pdf that can then be printed out or saved as a computer file.

Within a minute of depositing 14.5 BTC, worth over $500,000 at the time (and now worth over $700,000), it was all gone. Someone had swept the funds from Wendell’s wallet and, after playing blockchain hopscotch across multiple addresses, sent them to the Binance exchange. Source Link