PSA to orgs: if you use Microsoft 365, check your email logs for an email from mbsupport@microsoft.com
Microsoft are emailing tenant admin email addresses about a breach by Midnight Blizzard - you might not get the emails due to spam filtering etc.
https://www.reddit.com/r/microsoft/comments/1dowpf9/midnight_blizzard_microsoft_email_data_sharing/ #threatintel