I only found a few things related to this issue. One was a brute force attack, DDoS or you don't have the cnf option to skip DNS lookups set to "skip-name-resolve" (if that's still an option). Make sure all of your user, host and other information is all correct (including in the cnf/server side).
Some of these questions are pretty old though, so I'm not entirely sure what's really going on. If this is really the source of a repack, I would really suggest in starting your own MySQL server (your installed one) where ever you are hosting it.