Linear Congruential Generator

A very weak cryptographic algorithm created from pseudo-randomized numbers.

$X_{n+1}=(a{X}_n+c)\%m$ $X_n$ is the previous number or the seed if this is the first item of the sequence, $0<X_0<m$ $a$ is a randomly generated constant, $0<a<m$ $c$ is a randomly generated constant, $0\le c<m$ $m$ is a randomly generated constant, $0<m$

The LCG repeats itself. 634763476347634763476347. is a example output that it gives when $a=3,X_n=7,c=5,m=10$

Breaking LCG

If m is known to the attacker, and a,b are not known, then you can break LCG.

• LCG Recovering Parameters

Implementations

• RANDU

Vulnerabilities

• DVSorder Vulnerability