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MSRC

CVE-2021-26855

One-Click Microsoft Exchange On-Premises Mitigation Tool - March 2021

Monday, March 15, 2021

We have been actively working with customers through our customer support teams, third-party hosters, and partner network to help them secure their environments and respond to associated threats from the recent Exchange Server on-premises attacks. Based on these engagements we realized that there was a need for a simple, easy to use, automated solution that would meet the needs of customers using both current and out-of-support versions of on-premises Exchange Server.

Microsoft Exchange Server Vulnerabilities Mitigations - updated March 15, 2021

Friday, March 05, 2021

Update March 15, 2021: If you have not yet patched, and have not applied the mitigations referenced below, a one-click tool, the Exchange On-premises Mitigation Tool is now our recommended path to mitigate until you can patch. Microsoft previously blogged our strong recommendation that customers upgrade their on-premises Exchange environments to the latest supported version.