Heads up for folks...
There's a thread on Twitter (look for @patrickwardle) about encrypted APFS volumes created via Disk Utility in High Sierra having their password stored as the password hint. It does not happen if you use diskutil to create the encrypted volume.
https://twitter.com/martiano_/status/912733756020191232
https://twitter.com/felix_schwarz/status/915851372217683970
Looks like this was resolved in today's "supplemental update."
... wow.
Enter your E-mail address. We'll send you an e-mail with instructions to reset your password.