Is it possible to decrypt MD5 hashes?

Question

Someone told me that he has seen software systems that:

1. retrieve MD5 encrypted passwords from other systems;
2. decrypt the encrypted passwords and

Answer 1

No, he must have been confused about the MD5 dictionaries.

Cryptographic hashes (MD5, etc...) are one way and you can't get back to the original message with only the digest unless you have some other information about the original message, etc. that you shouldn't.