I get this message, update rkhunter and receive the same message.
I suggest you go read up first, pointers below.
BTW It does NOT tell me what is bad.
Then you should look in the rkhunter.log.
Rootkit Hunter (abbrev.: RKH) since version 1.2.9 comes with more documentation like a FAQ. We also set preferred
support options which leads to the rkhunter-users mailing list
archives and the RKH
FAQ.
Your question was already answered there (run hashupd) and a gazillion times I might add. If that ain't fixing it get on the rkhunter-users mailing list.