Explore an electromagnetic fault injection (EMFI) attack on the Trezor Bitcoin wallet that enables extraction of the recovery seed without opening the device. Learn how this technique allows cloning the wallet to steal bitcoins later, leaving no signs of tampering. Discover how a single comparison in the USB stack, common across many embedded systems, creates this vulnerability. Gain insights from Colin O'Flynn's 25-minute Black Hat conference talk on exploiting hardware vulnerabilities in cryptocurrency wallets and the broader implications for embedded system security.