Welcome to the last Patch Tuesday of 2023, wherein Microsoft lists fixes for 34 vulnerabilities, and one zero-day that was disclosed previously.

After an initial discussion about this month’s updates, we’ll offer our advice for devising a plan to handle patch management in a hybrid work environment. You can also register for our free Patch Tuesday webinar and listen to our experts break down Patch Tuesday updates in detail.

What is Patch Tuesday?  

Patch Tuesday falls on the second Tuesday of every month. On this day, Microsoft releases security and non-security updates for its OS and other related applications. Since Microsoft has upheld this process of releasing monthly updates since 2003, IT admins expect these updates and have time to gear up for them.

Why is Patch Tuesday important?  

Important security updates and patches to fix critical bugs or vulnerabilities are released on Patch Tuesday. Usually, zero-day vulnerabilities are also fixed during Patch Tuesday unless the vulnerability is critical and highly exploited, in which case an out-of-band security update is released to address that particular vulnerability.

December 2023 Patch Tuesday: Security updates lineup  

Security updates were released for the following products, features, and roles:

  • Windows Media

  • Microsoft Edge (Chromium-based)

  • Microsoft Office Outlook

  • Microsoft Dynamics

  • Microsoft Windows DNS

  • Azure Connected Machine Agent

  • Azure Machine Learning

  • Windows MSHTML Platform

  • Windows USB Mass Storage Class Driver

  • Windows Internet Connection Sharing (ICS)

  • Windows Win32K

  • Windows Kernel

  • Microsoft Bluetooth Driver

  • Windows DHCP Server

  • Windows ODBC Driver

  • Windows Kernel-Mode Drivers

  • XAML Diagnostics

  • Windows DPAPI (Data Protection Application Programming Interface)

  • Windows Telephony Server

  • Microsoft WDAC OLE DB provider for SQL

  • Microsoft Office Word

  • Windows Defender

  • Microsoft Power Platform Connector

  • Windows Local Security Authority Subsystem Service (LSASS)

  • Windows Cloud Files Mini Filter Driver

In addition, Microsoft has also republished six non-Microsoft CVEs. The details of those can be found here.

One zero-day patched  

December 2023’s Patch Tuesday witnessed one zero-day vulnerability which has been publicly disclosed. Let’s take a detailed look at the vulnerability:

This is a security vulnerability in AMD that can cause Information Disclosure and is rated as Important. “A division-by-zero error on some AMD processors can potentially return speculative data resulting in loss of confidentiality,” reported the National Vulnerability Database.

This non-Microsoft vulnerability has been added to Microsoft’s Security Update Guide since a Windows Update is required to mitigate it.

As for the mitigation, AMD has stated, “Developers can mitigate this issue by ensuring that no privileged data is used in division operations prior to changing privilege boundaries.”

Third-party updates released after last month’s Patch Tuesday  

Third-party vendors, such as Cisco, Google, SAP, VMWare, WordPress, and Atlassian, have also released updates this December.

Best practices to handle patch management in a hybrid work environment  

Many organizations today have opted to embrace remote work. This decision poses various challenges to IT admins, especially in terms of managing and securing distributed endpoints.

Here are a few pointers to simplify the process of remote patching:

  • Disable automatic updates because one faulty patch could bring down the whole system. IT admins can educate end users on how to disable automatic updates on their machines. Patch Manager Plus and Endpoint Central also have a dedicated patch, 105427, that can be deployed to endpoints to ensure that automatic updates are disabled.

  • Create a restore point—a backup or image that captures the state of the machines—before deploying big updates like those from Patch Tuesday.

  • Establish a patching schedule and keep end users informed about it. It is recommended to set up a time for deploying patches and rebooting systems. Let end users know what needs to be done on their end for trouble-free patching.

  • Test the patches on a pilot group of systems before deploying them to the production environment. This will ensure that the patches do not interfere with the workings of other applications.

Since many users are working from home, they all might be working different hours; in this case, you can allow end users to skip deployment and scheduled reboots. This will give them the liberty to install updates at their convenience and avoid disrupting their work. Our patch management products come with options for user-defined deployment and reboot.

  • Most organizations are deploying patches using a VPN. To stop patch tasks from eating up your VPN bandwidth, install Critical patches and security updates first. You might want to hold off on deploying feature packs and cumulative updates since they are bulky updates and consume a lot of bandwidth.

  • Schedule the non-security updates and security updates that are not rated Critical to be deployed after Patch Tuesday, such as during the third or fourth week of the month. You can also choose to decline certain updates if you feel they are not required in your environment.

  • Run patch reports to get a detailed view of the health status of your endpoints.

  • For machines belonging to users returning to the office after working remotely, check if they are compliant with your security policies. If not, quarantine them.

  • Install the latest updates and feature packs before deeming your back-to-office machines fit for production.

  • Take inventory of and remove apps that are now obsolete for your back-to-office machines, like remote collaboration software.

With Endpoint Central, Patch Manager Plus, or Vulnerability Manager Plus you can completely automate the entire process of patch management, from testing patches to deploying them. You can also tailor patch tasks according to your current needs. For a hands-on experience with either of these products, try a free, 30-day trial and keep thousands of applications patched and secure.

Want to learn more about Patch Tuesday updates? Join our experts as they break down this month’s Patch Tuesday updates and offer in-depth analysis. You can also ask our experts questions and get answers to all your Patch Tuesday questions. Register for our free Patch Tuesday webinar.

Ready, get set, patch!