Hint about incorrect RAILSVERSION

If the secret doesn't match, you might have set the wrong RAILSVERSION.
The difference is secret_token (Rails 3) vs. secret_key_base (Rails 4).

Author: wvu

modules/exploits/multi/http/rails_secret_deserialization.rb

@@ -247,7 +247,7 @@ def exploit
       if check_secret(match[2],match[3])
         print_good("SECRET matches! Sending exploit payload")
       else
-        fail_with(Failure::BadConfig, "SECRET does not match")
+        fail_with(Failure::BadConfig, "SECRET does not match, wrong RAILSVERSION?")
       end
     else
       print_warning("Caution: Cookie not found, maybe you need to adjust TARGETURI")