What Is a “Hash Collision” and Why Is It a Concern for Cryptographic Algorithms?

A hash collision occurs when two different input data sets produce the exact same output hash value. For a secure cryptographic hash function like SHA-256, finding a collision should be computationally infeasible.

If collisions were easy to find, an attacker could replace a valid transaction with a fraudulent one that generates the same block hash, undermining the security of the blockchain.

What Is a ‘Pre-Image Attack’ and How Does It Relate to Collision Resistance?
What Is the Difference between a Preimage Attack and a Collision Attack?
What Is the Difference between a Preimage Attack and a Collision Attack in Hashing?
What Is the Risk of a Hash Collision in a Signed Contract?
What Is a Collision Attack and How Does It Relate to Hash Function Security?
How Would a Successful Hash Collision Attack Impact the Financial Derivatives Market If a Blockchain Was Involved?
What Is a “Preimage Attack” and How Does It Differ from a Collision Attack?
What Is a Hash Collision and Why Is the Avalanche Effect Key to Preventing It in Cryptocurrencies?

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