Security News > 2021 > December > Microsoft December 2021 Patch Tuesday fixes 6 zero-days, 67 flaws
Today is Microsoft's December 2021 Patch Tuesday, and with it comes fixes for six zero-day vulnerabilities and a total of 67 flaws.
Microsoft has fixed 55 vulnerabilities with today's update, with seven classified as Critical and 60 as Important.
December's Patch Tuesday includes fixes for six zero-day vulnerabilities, with one actively exploited Windows AppX Installer vulnerability.
Microsoft classifies a vulnerability as a zero-day if it is publicly disclosed or actively exploited with no official fix available.
Microsoft also fixed five publicly disclosed zero-day vulnerabilities as part of the December 2021 Patch Tuesday that are not known to be exploited in attacks.
Below is the complete list of resolved vulnerabilities and released advisories in the December 2021 Patch Tuesday updates.
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