Security News > 2021 > April > Microsoft April 2021 Patch Tuesday fixes 108 flaws, 5 zero-days

Today is Microsoft's April 2021 Patch Tuesday, and with it comes five zero-day vulnerabilities and more Critical Microsoft Exchange vulnerabilities.
With today's update, Microsoft has fixed 108 vulnerabilities, with 19 classified as Critical and 89 as Important.
To make matters worse, Microsoft fixed four critical Microsoft Exchange vulnerabilities that the NSA discovered.
As part of today's Patch Tuesday, Microsoft has fixed four publicly disclosed vulnerabilities and one actively exploited vulnerability.
Microsoft Exchange admins are not getting any rest as four more Critical remote code execution vulnerabilities discovered by the NSA were fixed in Microsoft Exchange today.
Below is the full list of resolved vulnerabilities and released advisories in the April 2021 Patch Tuesday updates.
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