Question

Given a message and its n-bit hash result, the expected workload of finding a message that hashes to the same value is of the order _______________

(a) 2^(n/2)

(b) 2^(n-1)

(c) 2^(n)

(d) 2^(2n)

I got this question during an internship interview.

The doubt is from Whirlpool Algorithm topic in chapter Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security

Answer 1

Correct option is (c) 2^(n)

The explanation: When the message and hash value are provided, the workload turns out to be 2^n.