How Does Elliptic Curve Digital Signature Algorithm (ECDSA) Protect against Preimage Attacks?

ECDSA is a digital signature algorithm, not a hash function, but it relies on cryptographic hash functions for signing. The hash of the message is signed, not the message itself.

The security of the private key, which is used to generate the public key, is protected by the mathematical difficulty of reversing the elliptic curve multiplication, not the hash function's preimage resistance. The hash function ensures message integrity before signing.

What Is the Risk of an Attacker Finding the Private Key Once the Public Key Is Known?
What Mathematical Problem Is the Security of ECDSA Based Upon?
How Is a Second-Preimage Attack Different from a First-Preimage Attack?
What Is the Mathematical Basis for the One-Way Function?
What Is a Second-Preimage Attack and How Does It Differ from a First-Preimage Attack?
What Is the Risk to ECDSA from Quantum Computing?
How Does the Elliptic Curve Digital Signature Algorithm (ECDSA) Relate to Public Key Security?
What Is the Role of the “Elliptic Curve” in the Security of ECDSA?

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