I got a voting correction "out of the blue". It's not much so I don't care about the rep change very much. But I was wondering where (which answers/questions) and why it was applied. I haven't been very active in the past few weeks, and there was no significant reputation change so the sudden correction is rather strange. How do I get more information?
Essentially - a user was found voting things randomly across the network to try to earn badges. The user's votes were invalidated across the network, resulting in a 'serial voting corrected' message. The serial voting was unusually across the network and spread across many users - hence individual reputation change being for 1-2 votes unlike the more typical serial voting involving many votes for one user on one site.
I can't really share anything other than what's on the MSE post but this is probably the reason.