Zscaler, working with Microsoft through their MAPP program, has proactively deployed protection for the following 4 vulnerabilities included in the October 2020 Microsoft security bulletins. Zscaler will continue to monitor exploits associated with all vulnerabilities in the October release and deploy additional protections, as necessary.

CVE-2020-16898 – Windows TCP/IP Remote Code Execution Vulnerability

Severity: Critical

Affected Software

Windows 10 Version 1803 for 32-bit Systems
Windows 10 Version 1803 for x64-based Systems
Windows 10 Version 1803 for ARM64-based Systems
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
Windows Server, version 1909 (Server Core installation)
Windows 10 Version 1709 for 32-bit Systems
Windows 10 Version 1709 for x64-based Systems
Windows 10 Version 1709 for ARM64-based Systems
Windows 10 Version 1903 for 32-bit Systems
Windows 10 Version 1903 for x64-based Systems
Windows 10 Version 1903 for ARM64-based Systems
Windows Server, version 1903 (Server Core installation)
Windows 10 Version 2004 for 32-bit Systems
Windows 10 Version 2004 for ARM64-based Systems
Windows 10 Version 2004 for x64-based Systems
Windows Server, version 2004 (Server Core installation)

A remote code execution vulnerability exists when the Windows TCP/IP stack improperly handles ICMPv6 Router Advertisement packets. An attacker who successfully exploited this vulnerability could gain the ability to execute code on the target server or client. To exploit this vulnerability, an attacker would have to send specially crafted ICMPv6 Router Advertisement packets to a remote Windows computer.

CVE-2020-16899 – Windows TCP/IP Denial of Service Vulnerability

Severity: Important

Affected Software

Windows 10 Version 1803 for 32-bit Systems
Windows 10 Version 1803 for x64-based Systems
Windows 10 Version 1803 for ARM64-based Systems
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
Windows Server, version 1909 (Server Core installation)
Windows 10 Version 1709 for 32-bit Systems
Windows 10 Version 1709 for x64-based Systems
Windows 10 Version 1709 for ARM64-based Systems
Windows 10 Version 1903 for 32-bit Systems
Windows 10 Version 1903 for x64-based Systems
Windows 10 Version 1903 for ARM64-based Systems
Windows Server, version 1903 (Server Core installation)
Windows 10 Version 2004 for 32-bit Systems
Windows 10 Version 2004 for ARM64-based Systems
Windows 10 Version 2004 for x64-based Systems
Windows Server, version 2004 (Server Core installation)

A denial of service vulnerability exists when the Windows TCP/IP stack improperly handles ICMPv6 Router Advertisement packets. An attacker who successfully exploited this vulnerability could cause a target system to stop responding. To exploit this vulnerability, an attacker would have to send specially crafted ICMPv6 Router Advertisement packets to a remote Windows computer. The vulnerability would not allow an attacker to execute code or to elevate user rights directly.

CVE-2020-16907 – Win32k Elevation of Privilege Vulnerability

Severity: Important

Affected Software

Windows 10 Version 1803 for 32-bit Systems
Windows 10 Version 1803 for x64-based Systems
Windows 10 Version 1803 for ARM64-based Systems
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
Windows Server, version 1909 (Server Core installation)
Windows 10 Version 1709 for 32-bit Systems
Windows 10 Version 1709 for x64-based Systems
Windows 10 Version 1709 for ARM64-based Systems
Windows 10 Version 1903 for 32-bit Systems
Windows 10 Version 1903 for x64-based Systems
Windows 10 Version 1903 for ARM64-based Systems
Windows Server, version 1903 (Server Core installation)
Windows 10 Version 2004 for 32-bit Systems
Windows 10 Version 2004 for ARM64-based Systems
Windows 10 Version 2004 for x64-based Systems
Windows Server, version 2004 (Server Core installation)

An elevation of privilege vulnerability exists in Windows when the Windows kernel-mode driver fails to properly handle objects in memory. An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. To exploit this vulnerability, an attacker would first have to log on to the system. An attacker could then run a specially crafted application that could exploit the vulnerability and take control of an affected system.

CVE-2020-16913 – Win32k Elevation of Privilege Vulnerability

Severity: Important

Affected Software

Windows 10 Version 1803 for 32-bit Systems
Windows 10 Version 1803 for x64-based Systems
Windows 10 Version 1803 for ARM64-based Systems
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
Windows Server, version 1909 (Server Core installation)
Windows 10 Version 1709 for 32-bit Systems
Windows 10 Version 1709 for x64-based Systems
Windows 10 Version 1709 for ARM64-based Systems
Windows 10 Version 1903 for 32-bit Systems
Windows 10 Version 1903 for x64-based Systems
Windows 10 Version 1903 for ARM64-based Systems
Windows Server, version 1903 (Server Core installation)
Windows 10 Version 2004 for 32-bit Systems
Windows 10 Version 2004 for ARM64-based Systems
Windows 10 Version 2004 for x64-based Systems
Windows Server, version 2004 (Server Core installation)