Microsoft October Patch Tuesday: Fixes for 4 Zero-Day Vulnerabilities Included in the 71 updates, Microsoft Patch Tuesday will include patches for 4 Zero-Day vulnerabilities. The zero-day items include: Privilege escalation vulnerability in the Windows kernel. (https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-40449) Security feature bypass of Firewall Rules for the Windows AppContainer. (https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-41338) Windows DNS Server RCE flaw. (https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-40469) Windows Kernel privilege escalation. (https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-41335) In addition to the Zero-Day vulnerabilities, this Microsoft update patches a number of other vulnerabilities and 3 critical flaws, one in MSWord and 2 in Hyper-V, which enabled remote code execution if executed. The remaining updates in the release include less severe vulnerabilities across the Microsoft collection. This release is available worldwide. If your computer has not yet received the updates, or your use manual installation, you should update your systems at the earliest convenience to avoid security risks.