Security News > 2024 > February > Microsoft: New critical Exchange bug exploited as zero-day

Microsoft warned today in an updated security advisory that a critical vulnerability in Exchange Server was exploited as a zero-day before being fixed during this month's Patch Tuesday.
"The leaked credentials can then be relayed against the Exchange server to gain privileges as the victim client and to perform operations on the Exchange server on the victim's behalf."
Microsoft announced today that Extended Protection will be automatically enabled by default on all Exchange servers after installing this month's 2024 H1 Cumulative Update.
Admins can use the ExchangeExtendedProtectionManagement PowerShell script to activate EP on previous versions of Exchange Server, such as Exchange Server 2016.
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