Reseller News Join Reseller News Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.Sign up now The Microsoft Exchange Server hack: A timeline Research shows plenty of unpatched systems remain. Here's how the attacks unfolded, from discovery of vulnerabilities to today's battle to close the holes. Credit: Dreamstime On March 2, 2021 Microsoft detected multiple zero-day exploits being used to attack on-premises versions of Microsoft Exchange Server. Over the next few days, over 30,000 organisations in the US were attacked as hackers used several Exchange vulnerabilities to gain access to email accounts and install web shell malware, giving the cyber criminals ongoing administrative access to the victims' servers.