In the Schnorr Digital Signature Scheme, which of the following statements correctly explains why reusing the same random value k for different messages compromises the private key xA?

Question

Answer

Because the value of r becomes identical for both signatures, allowing the attacker to compute h(m1||r)-h(m2||r) directly.

Answer

Because identical k values invalidate the hash function’s collision resistance property.

Answer

Because knowing two signatures (r,s1)and (r,s2)with the same kallows solving the linear relation s1-s2=(xA)(h1-h2) mod q to recover xA.

Answer

Because kdetermines the generator α, and reusing it changes the base of the exponentiation.

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In the Schnorr Digital Signature Scheme, which of the following statements corre...

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