Patch Tuesday: October 2020 | Kaseya


Any individual that has spent time on a personal computer knows what an update or patch is. A patch is a set of changes or updates done to a computer program or application — everything from the operating system (OS) to business apps and browsers. This is mostly done to fix a software bug or error or to provide new features and enhancements. Patching of software is important since security patches address software vulnerabilities that cybercriminals might exploit to gain unauthorized access to your device and your data.

What Is Patch Tuesday?

Microsoft Patch Tuesday is the second Tuesday of every month on which Microsoft releases security-related updates for its Windows OS, browsers and business applications. The other updates, not related to security, are released on the fourth Tuesday of every month. Sometimes, Microsoft releases an out-of-band (OOB) update for an emergency security issue that is not published specifically on the second Tuesday, but could be published on any day of the month.

When Did Patch Tuesday Begin?

Patch Tuesday was introduced by Microsoft in October 2003 to mainly reduce the cost of distributing patches. Tuesday was specifically chosen as the optimal day of the week so as to allow users to apply patches over the week. Monday was left free to address any issues that arose over the preceding weekend.

Severity Rating System for Vulnerabilities

To help customers understand the importance of applying a particular patch, Microsoft has published a severity rating system that rates each vulnerability according to the worst theoretical outcome should that vulnerability be exploited.

Rating Description
Critical It is recommended that critical updates are applied quickly. A vulnerability is rated critical when its exploitation could allow code execution without user interaction.
Important A vulnerability that could result in the compromise of confidentiality and integrity of user data. Microsoft recommends that customers apply important updates at the earliest opportunity.
Moderate A vulnerability that is mitigated to a significant degree by certain factors such as default configuration, auditing and authentication requirements. Microsoft recommends that customers consider applying the security update.
Low A vulnerability that is extremely difficult to exploit or has minimal impact.

Patch Tuesday October 2020 Updates

Microsoft provides Patch Tuesday updates in its Security Update Guide portal. Each update also comes with a set of release notes. (See this month’s release notes at the bottom of this blog.)

The Common Vulnerabilities and Exposure (CVE) ID is a format in which each vulnerability is disclosed and cataloged in the National Vulnerability Database (NVD). Vulnerabilities in the NVD have a criticality rating ranging from 1 (lowest) to 10 (highest).

For the October 2020 Patch Tuesday, a total of 87 CVEs were released, with 11 of them rated “Critical.” The October security updates are for the following Microsoft software:

  • Microsoft Windows
  • Microsoft Office and Microsoft Office Services and Web Apps
  • Microsoft JET Database Engine
  • Azure Functions
  • Open Source Software
  • Microsoft Exchange Server
  • Visual Studio
  • PowerShellGet
  • Microsoft .NET Framework
  • Microsoft Dynamics
  • Adobe Flash Player
  • Microsoft Windows Codecs Library

Below are the CVE details of the “Critical” vulnerabilities in this month’s update.

ID Title Rating Description
CVE-2020-16891 Windows Hyper-V Remote Code Execution Vulnerability Critical A remote code execution vulnerability exists when Windows Hyper-V on a host server fails to properly validate input from an authenticated user on a guest operating system.
CVE-2020-16898 Windows TCP/IP Remote Code Execution Vulnerability Critical A remote code execution vulnerability exists when the Windows TCP/IP stack improperly handles ICMPv6 Router Advertisement packets.
CVE-2020-16911 GDI+ Remote Code Execution Vulnerability Critical A remote code execution vulnerability exists in the way that the Windows Graphics Device Interface (GDI) handles objects in memory.
CVE-2020-16915 Media Foundation Memory Corruption Vulnerability Critical A memory corruption vulnerability exists when Windows Media Foundation improperly handles objects in memory.
CVE-2020-16923 Microsoft Graphics Components Remote Code Execution Vulnerability Critical A remote code execution vulnerability exists in the way that Microsoft Graphics Components handle objects in memory.
CVE-2020-16947 Microsoft Outlook Remote Code Execution Vulnerability Critical A remote code execution vulnerability exists in Microsoft Outlook software when the software fails to properly handle objects in memory.
CVE-2020-16951 Microsoft SharePoint Remote Code Execution Vulnerability Critical A remote code execution vulnerability exists in Microsoft SharePoint when the software fails to check the source markup of an application package.
CVE-2020-16952 Microsoft SharePoint Remote Code Execution Vulnerability Critical A remote code execution vulnerability exists in Microsoft SharePoint when the software fails to check the source markup of an application package.
CVE-2020-16967 Windows Camera Codec Pack Remote Code Execution Vulnerability Critical A remote code execution vulnerability exists when the Windows Camera Codec Pack improperly handles objects in memory.
CVE-2020-16968 Windows Camera Codec Pack Remote Code Execution Vulnerability Critical A remote code execution vulnerability exists when the Windows Camera Codec Pack improperly handles objects in memory.
CVE-2020-17003 Base3D Remote Code Execution Vulnerability Critical A remote code execution vulnerability exists when the Base3D rendering engine improperly handles memory.

The complete details of all 87 October 2020 security updates can be found on the Microsoft’s Security Update Guide page. The release notes can be found here as well.

We highly recommend that you apply these patches at the earliest, within 30 days of release at the latest.

Learn more about patching in Kaseya VSA here.