Recently, at CT-RSA 2004, Phan [14] suggested the related-key attack on three-key triple-DES under some chosen related-key
condition. The attacks on three-key triple-DES require known plaintext and ciphertext queries under a chosen related-key condition.
He also presented related-key attacks on two-key triple-DES and DES-EXE, which require known plaintext and adaptively chosen
ciphertext queries under some related-key conditions. In this paper, we extended the previous attacks on the triple-DES and
DES-EXE with various related-key conditions. Also we suggest a meet-in-the-middle attack on DES-EXE.