Re:“Quantum-Safe” Crypto Hacked by 10-Year-Old PC
by athrowaway3z on Friday August 19, 2022 @04:15PM
(#32525484)
'breaking' a hash can mean many different things.
Among many others, two types of attacks are:
- a specific prefix/suffix data can be created to force a collision.
- A message of exactly N bytes can quickly create a collision.
Both attacks would be reported as a hash being broken.
But its assumed to be unlikely that a well designed hash would have a flaw that breaks the hash in both ways.
Keyword being assumed. But with good reason.
AFAIK sha has only been broken by a variable length suffix attack.
With sha2(sha2()) it would have to be broken both ways.
- a specific prefix/suffix data can be created to force a collision.
- A message of exactly N bytes can quickly create a collision.
Both attacks would be reported as a hash being broken. But its assumed to be unlikely that a well designed hash would have a flaw that breaks the hash in both ways. Keyword being assumed. But with good reason.
AFAIK sha has only been broken by a variable length suffix attack.
With sha2(sha2()) it would have to be broken both ways.