WorldsFirstSha2Vulnerability

Sha256 vulnerability for full rounds. Free-start collision attack + circular hash attack(new type of hash attack).

Proof

Run proof.py to check my work

Concepts

Free-start collision attack

A collision attack where hackers cannot control the input hash.

Circular hash attack

Finding input_hash and message_block which makes input_hash=output_hash. In certain cases, it can result infinite set of collisions by chaining arbitrary number of circular blocks. So, this attack makes one hash value permanently vulnerable to collisions. So, I decided not to publish another works.

Attack methods

I developed an entirely new type of cryptanalysis theory to achieve this. It has a similar form comparing to differential analysis.