How Is a Hash Function's "Pre-Image Resistance" Relevant to Blockchain Security? ▴ Learn

How Is a Hash Function’s “Pre-Image Resistance” Relevant to Blockchain Security?

Pre-image resistance means that given a hash output, it is computationally infeasible to find the original input (the pre-image). In Bitcoin, transaction data is the input, and the hash is the output used in the block structure.

This property ensures that malicious actors cannot reverse-engineer a valid block hash to forge a block without performing the necessary Proof-of-Work, thus protecting the integrity of the ledger.

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