I’ve been noticing spammy webmentions coming in to my site from twitter. I’ve protected my tweets, which I hope will solve the problem moving forward.
At the moment I’m just using brid.gy and webmention.io to handle webmentions. I may need to start digesting incoming webmentions and storing them some place, rather than using the raw incoming JSON from webmention.io. This way I could block stuff, if necessary.