Andrewl.us SDDecoder Junior

SDDecoder Junior
Author: andrewl.us
Language: C/C++
Protection: GF(2) Equations

Very interesting one, linear system of equations over GF(2), solved using Gauss Elimination over GF(2). Plus some other GF(2) arithmetics are in the challenge. The crackme is a part of a quest to learn more about MQ schemes and eventually break SDDecoder. My solution to the SDDecoder Junior is here

Mucki's Protector II

Mucki's Protector II
Author: Mucki
Language: Assembler
Protection: RSA,Custom Packer,Small VM

This one uses a custom packer and a small RSA(32bit). Read my solution here. It has a small unpacker for the packer also.

Pineware_002 - Keygenme

Pineware_002 - Keygenme
Author: Ultimate Pinecone's
Language: Assembler
Protection: Obfusticated VM, Befunge language.

The crackme is actually a Befunge intepreter, with some additional commands. Algorithm itself is very trivial calculations.

Read my solution here.