In August, Mastodon 2.4.4 was released which contains two fixes for security vulnerabilities.
Today, 39.5% of all Mastodon instances which show their version number are still running vulnerable Mastodon < 2.4.4.
We already checked this twice:
– 10/1/18: 42% vulnerable
– 8/23/18: 38.6% vulnerable
Either the remaining instances are all unmaintained or admins refuse to update.