DES · FIPS 46-3 (withdrawn 2005-05-19)
Step the real 16-round DES one round at a time, replace its round function with one that destroys information and watch the network invert anyway, break double DES by meeting in the middle, and lift a session cookie out of CBC through a 64-bit block collision.
Not production cryptography. DES is broken and has been withdrawn since 2005; nothing here is constant-time, and the CBC in this page is unauthenticated. Every cipher operation on this page is real — no simulated math — and the two places where a result is arranged rather than found say so on screen, permanently.