On the current spam wave some of you experience on the Fediverse: I think @stux is right by suspecting it might be one or more 3rd party apps that got hacked or are leaking authentication tokens.
So. Go to your account settings and check the "Authorized Apps" part. Revoke the permissions of apps you don't use anymore. Consider it housekeeping and make it a regular Todo :)
@jwildeboer @stux
Finally enabled 2fa (been meaning to do that for a while) and cleaned out every authorized app I don't actively use.
I wonder why the authorization isn't time limited