3 ms·
True, but the attack already builds upon modifying the state machine to get the same end result, creating data to allow for a specific prefix (e.g. always getti
by consp 10y ago
True, but the attack already builds upon modifying the state machine to get the same end result, creating data to allow for a specific prefix (e.g. always getting the desired intermediary state) should also be doable in some form of this attack.
- 0x0 10y agoWould it help if we padded the prefix so that the rest of the files are aligned to the block size of SHA1 (512bits), so that the crafted blocks are still block-aligned? Or does the different initial state (due to a different prefix) break any chance of re-colliding with these specific files? (i.e. you'll have to run the full brute force attack again with a valid git blob header as a common prefix?)
- Klathmon 10y agoIt's content specific. Changing anything before that point ruins the whole attack. So yeah you'd need to do the whole attack again but with the prefix.