About

Below are some problems related to computer security (specifically poorly implemented security). Do Them. You are free to use any language and environment you like to complete them. The problems require familiarity with programming, but not necessarily with applied cryptography or computer security in general. An understanding of how some of the algorithms and tools in the problems work will be of use, so as a starting point you can find some resources to help you begin here. If this topic is new to you, you may want to start with the Tutorial Problems.

Problems

AES-CTR with Nonce Reuse

Can you exploit a reused nonce?

Solved by 82
Double Strength Affine

A slight security upgrade, is it enough?

Solved by 80
ECDSA Nonce Recovery

Nonce reuse leading to private key recovery, this time with elliptic curves

Solved by 78
Elliptic Curve Private Key Recovery

Given the public parameters of an elliptic curve, recover the poorly chosen private key

Solved by 75
previous 1 2 3 4 5 6 7 8 9 10 11 next