A “security incident” is behind AO3’s outage.

The fanworks platform announced yesterday that it could be down for four weeks, and now we know why. Details about the security incident itself haven’t been shared, but no AO3 data has been deleted, and the site runners currently don’t believe that user account information was stolen, but are “unable to rule it out.” > “Earlier today, we detected evidence of a security incident on AO3. We are still in the early stages of response to this security incident and determining its scope. AO3 will remain down while we continue investigating and addressing what has been found so far.”