Security News > 2021 > November > Microsoft November 2021 Patch Tuesday fixes 6 zero-days, 55 flaws
Today is Microsoft's November 2021 Patch Tuesday, and with it comes fixes for six zero-day vulnerabilities and a total of 55 flaws.
The actively exploited vulnerabilities are for Microsoft Exchange and Excel, with the Exchange zero-day used as part of the Tianfu hacking contest.
Microsoft has fixed 55 vulnerabilities with today's update, with six classified as Critical and 49 as Important.
November's Patch Tuesday includes fixes for six zero-day vulnerabilities, two actively exploited against Microsoft Exchange and Microsoft Excel.
The Microsoft Excel CVE-2021-42292 was discovered by the Microsoft Threat Intelligence Center and has been actively used in malicious attacks.
Below is the complete list of resolved vulnerabilities and released advisories in the November 2021 Patch Tuesday updates.
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Related Vulnerability
| DATE | CVE | VULNERABILITY TITLE | RISK |
|---|---|---|---|
| 2021-11-10 | CVE-2021-42292 | Unspecified vulnerability in Microsoft products Microsoft Excel Security Feature Bypass Vulnerability | 0.0 |