Security News > 2021 > October > Microsoft October 2021 Patch Tuesday fixes 4 zero-days, 71 flaws
Today is Microsoft's October 2021 Patch Tuesday, and with it comes fixes for four zero-day vulnerabilities and a total of 74 flaws.
Microsoft has fixed 74 vulnerabilities with today's update, with three classified as Critical, and 70 as Important, and one as Low.
October's Patch Tuesday includes fixes for four zero-day vulnerabilities, with a Win32k Elevation of Privilege Vulnerability vulnerability known to have been actively exploited in attacks.
Microsoft classifies a vulnerability as a zero-day if it is publicly disclosed or actively exploited with no official fix available.
Microsoft also fixed three other publicly disclosed vulnerabilities that are not known to be exploited in attacks.
Below is the complete list of resolved vulnerabilities and released advisories in the October 2021 Patch Tuesday updates.
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