Making Cybersecurity … Fun

Cracking RSA with low factors

So, what’s the generic skill that you need to be good at Cybersecurity? Well, it helps to be a problem solver, as every new cyber attack can bring something new, and a new puzzle to solve. So how do you keep your skills high? Well, one way is to undertake CTFs (Capture The Flags), and where we are given puzzles to solve, and then have to find the flags associated with the puzzle. These flags are then associated with points.

But, there’s a strong educational foundation within the CTFs, and where (hopefully) the person taking the challenge will learn a little bit about the methods they are using. So, let’s see if we can learn a little bit about RSA, and solve this puzzle:

Bob sends Alice a cipher using the RSA method. The cipher is 19751341666776829065145843236986750288541130546660759092487484411847198444616087576014984895888571809225722300519581208873003514281409162845915831387840637819795193966050551817621046535516655170078018847403058110927999276083560649057732777457816307053213770302914981171661624894526596565625046726300570757509 and the public modulus is…