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Comment by srcmap | Hacker News Reader

"use fast graphics cards, which have the potential to shave the average cost of factorizing a vulnerable 2048-bit key to $2,000."

Anyone has estimated the impact of this on crypto currency or crypto wallet system?

It would be interesting to see how many if any of the public keys use n crypto currency systems are potentially impacted by this type of hack.

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Bitcoin and most other cryptocurrencies use elliptic-curve cryptography (in particular, ECDSA) instead of RSA. So this flaw is not applicable to Bitcoin. (One reason for Bitcoin using ECDSA instead of RSA is that ECDSA keys are significantly smaller than RSA keys for the same security level.)

In addition, in Bitcoin, the ECDSA public key for unspent transaction outputs is not itself stored in the blockchain; only the SHA256 hash of the key is stored. If the same private key isn't reused (and reuse is discouraged for privacy reasons), an attacker wouldn't have access to the public key.

Recently many bitcoin transactions are P2SH (addresses starting with 3) and it that case the address is not directly linked to any public key at all (1-addresses are hashes of ECDSA public keys, 3-addresses are hashes of arbitrary bytecode which validates the signature and is supplied together with the signature)

Even if they had used RSA keys, the vulnerability here is in a particular hardware/firmware implementation of the algorithm, not in RSA itself.

That was my immediate question and sadly TFA doesn’t address it.

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