CRITICAL 9.9 Microsoft

CVE-2021-26424

Windows TCP/IP Remote Code Execution Vulnerability

Microsoft Security Update 2021-Aug: Windows TCP/IP Remote Code Execution Vulnerability

Affected Products

Windows 10 Version 1809 for 32-bit Systems
Windows 10 Version 1809 for x64-based Systems
Windows 10 Version 1809 for ARM64-based Systems
Windows Server 2019
Windows Server 2019 (Server Core installation)
Windows 10 Version 1909 for 32-bit Systems
Windows 10 Version 1909 for x64-based Systems
Windows 10 Version 1909 for ARM64-based Systems

References

Published: 2021-08-10 · Source: Microsoft · Feed updated: 2026-08-10

This critical severity vulnerability with a CVSS score of 9.9 was published on 2021-08-10 via Microsoft. EPSS score: 58.9% (top 1% of all CVEs by exploitation probability). Affected: Windows 10 Version 1809 for 32-bit Systems, Windows 10 Version 1809 for x64-based Systems, Windows 10 Version 1809 for ARM64-based Systems and 5 more.

Risk Timeline

CVE Disclosed2021-08-10 · 1825 days ago

Remediation Resources

Official Advisory

msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26424

NVD / MITRE

nvd.nist.gov/vuln/detail/CVE-2021-26424

Related Vulnerabilities

CVE	Title	Severity	CVSS
CVE-2021-34458	Windows Kernel Remote Code Execution Vulnerability	CRITICAL	9.9
CVE-2026-57092	Microsoft Windows VMSwitch Elevation of Privilege Vulnerability	CRITICAL	9.9
CVE-2021-26432	Windows Services for NFS ONCRPC XDR Driver Remote Code Execution Vulnerability	CRITICAL	9.8
CVE-2023-36910	Microsoft Message Queuing (MSMQ) Remote Code Execution Vulnerability	CRITICAL	9.8
CVE-2023-36911	Microsoft Message Queuing (MSMQ) Remote Code Execution Vulnerability	CRITICAL	9.8
CVE-2023-35385	Microsoft Message Queuing (MSMQ) Remote Code Execution Vulnerability	CRITICAL	9.8

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