Ledger posted an update for their ongoing HW bounty totalling 2.337 BTC.
Ledger’s first CTF (Capture The Flag) event has officially ended! We’d like to take this opportunity to thank all the individuals and teams that participated to the contest. We received more than 500 answers, and while most participants wished to remain anonymous, we believe that the techniques employed indicate many were security professionals.
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All the finishers qualified (and a few others) to try & extract the private key from a dedicated Hardware Bounty, which they received mid april. More than 100 devices with the same key has been sent. The dedicated bounty is a simple USB device which computes a public key from a private key (a simple scalar multiplication).This public key is sent back using the USB connection. There are a few countermeasures in place to protect the private key.