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Merkle Proof Bug

Posted on June 30, 2025
Kaizen Global

By Kaizen Global

Affordable SEO & Digital Marketing Services | Kaizen Global

def verify_proof(proof, root, leaf):
    hash = leaf
    for sibling in proof:
        hash = hashlib.sha256(hash + sibling).hexdigest()
    return hash == root

This blockchain Merkle proof function is broken. Why does it fail to verify correct proofs? Explain how byte order and hashing affect blockchain Merkle tree logic.



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Hi there,

If you’re seeing issues verifying a proof, double-check the byte handling and hash order, small mistakes there can break the logic.

If it’s a generic example, it might not be a valid use case.

- Bobby

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