XSL attack
In 2004 it was shown by one of the cryptanalysts, that the algorithm does not perform as described in its published paper. In addition, the method requires long effort. Unless shortened, the technique does not reduce the effort to break AES in comparison to a brute force attack. Therefore, it does not affect the real-world security of block ciphers in the near future. However, the attack has caused some experts to insert complexities in the algebraic simplicity of the current AES.