Unsupported current Keepass 2.x files .kdbx ?

[wirepatch]

Unfortunately type 2.x .kdbx files yield:

# ~/john/run/keepass2john a.kdbx 
! a.kdbx : File version '40000' is currently not supported!

[encolpe]

It means it is a keybase DB version 4. You need a more recent version of keepass2john.
You cat get the last release or compile from the repo (https://github.com/openwall/john).

But it will be useless as hashcat doesn't support keepass 4 db: hashcat/hashcat#2195

The best you can do at that point is to use directly john:

 ~/Documents/crackpass/john/run/john --format=keepass CrackThis.txt