from what I have heard lately there seems to be some type of bot attack on phpbb boards going around. It even apparently hit phpbb.com lately as well.
they can't get in, but they keep banging on the door until they hit the max number of retries and then move on to the next username and/or the next board.
I would guess that it is scraping usernames and maybe just admin names and then trying to brute force the password.
I'm baaaaaccckkkk. still doing work on donation basis. PM your needs.
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