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Calling a PRNG in the same initial state, either without seeding it explicitly or by seeding it with the same value, results in generating the same sequence of random numbers in different runs of the program. If a PRNG function is called 10 times consecutively to produce a sequence of 10 random numbers without being seeded, running the code for the first time produces the sequence S = {r1, r2, r3, r4, r5, r6, r7, r8, r9, r10}. If the PRNG is subsequently seeded with the same initial seed value, then it will generate the same sequentce sequence S.
As a result, after the first run of an improperly seeded PRNG, an attacker can predict the sequence of random numbers that will be generated in the future runs. Improperly seeding or failing to seed the PRNG can lead to vulnerabilities, especially in security protocols.
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