Microsoft says 92% of Exchange servers have been patched or mitigated
Microsoft Exchange servers are getting patched and mitigated at a good rate, but servers are still at risk.
What you need to know
- 92% of vulnerable Exchange servers have been patched or mitigated.
- That marks a 43% improvement over last week.
- Patching a server does not protect them if they have already been compromised.
Microsoft states that 92% of vulnerable Exchange servers have been patched or mitigated. That figure shows an improvement of 43% over last week, according to Microsoft. The company states that there is strong momentum for on-premises Exchange server updates.
It's important to note that patching or mitigating a vulnerability does not protect servers that have already been compromised. IT admins need to check to see if their systems have been exploited.
Microsoft has taken several steps to address the widespread attack on its Exchange server software. The company released an emergency fix for the vulnerability and released a one-click mitigation tool. Microsoft also updated Microsoft Defender to address one vulnerability.
Our work continues, but we are seeing strong momentum for on-premises Exchange Server updates:
• 92% of worldwide Exchange IPs are now patched or mitigated.
• 43% improvement worldwide in the last week. pic.twitter.com/YhgpnMdlOXOur work continues, but we are seeing strong momentum for on-premises Exchange Server updates:
• 92% of worldwide Exchange IPs are now patched or mitigated.
• 43% improvement worldwide in the last week. pic.twitter.com/YhgpnMdlOX— Security Response (@msftsecresponse) March 22, 2021March 22, 2021
Threat actors jumped on the opportunity to go after unpatched Microsoft Exchange servers. Check Point Research saw exploitation attempts on organizations double every 2-3 hours over a 24-hour period earlier this month.
Researchers at F-Secure said that servers are being hacked faster than they can count. In a report from March 19, Antii Laaktikainen, senior security consultant at F-Secure said, "Tens of thousands of servers have been hacked around the world. They're being hacked faster than we can count. Globally, this is a disaster in the making" (via ZDNet.
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Sean Endicott is a News Writer at Windows Central, where he covers Windows 11, Surface hardware, Microsoft 365, AI, apps, and the broader PC ecosystem. Since joining the site in 2017, he has written well over a thousand articles across the Microsoft landscape, covering breaking news, analysis, and feature reporting.
He writes Windows Wrap, a weekly column covering the biggest stories in Windows and the PC industry, and what they mean for the platform going forward.
Before joining Windows Central full-time, Sean worked in journalism and media production after earning a First Class degree in Broadcast Journalism from Nottingham Trent University. Outside of tech, he is an award-winning American football coach based in Nottingham, England, and was named BAFCA Youth Coach of the Year in 2024.
