Japanese researchers break 41 out of 64 steps of SHA256 with preimage attack.
by
TheoryOfBitcoin
on 17/12/2013, 02:06:13 UTC
This affects Bitcoin massively because bitcoin uses SHA256 hashes for transaction IDs and blocks. A preimage attack is when you can find a value that has a specific hash value. For example, when researchers break the full 64 steps of SHA256, they will be able to double spend transactions and mine blocks near infinitely fast.