Rackspace has issued another update to its recent security incident. It now discloses that this was a ransomware attack:
We appreciate your patience as we continue to work through the security issues that have affected our Hosted Exchange environment. As you know, on Friday, December 2nd, 2022, we became aware of suspicious activity and immediately took proactive measures to isolate the Hosted Exchange environment to contain the incident. We have since determined this suspicious activity was the result of a ransomware incident.
Read more of the update on Rackspace’s web site. Rackspace does not indicate who the threat actors are.