Last May, Mastodon server Kolektiva.social was compromised when one of the server’s admins had their home raided by the FBI for unrelated charges. All of their electronics, including a backup of the instance database, were seized.

According to Kolektiva, the seized database, now in the FBI’s possession, includes personal information such as email addresses, hashed passwords, and IP addresses from three days prior to the date the backup was made. It also includes posts, direct messages, and interactions involving a user on the server.

https://www.eff.org/deeplinks/2023/07/fbi-seizure-mastodon-server-wakeup-call-fediverse-users-and-hosts-protect-their