February 2023 Patch Tuesday comes with fixes for 77 vulnerabilities, including 3 zero days

This Patch Tuesday, as a Valentine's Day present, Microsoft has gifted us fixes for a total of 77 vulnerabilities, including three zero days. With all of the zero-day vulnerabilities being actively exploited, admins need to implement these patches as soon as possible.

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 operating system and other related applications. Since Microsoft has upheld this process of releasing updates in a periodic manner, 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.

February 2023 Patch Tuesday: Security updates lineup  

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

  • .NET and Visual Studio

  • .NET Framework

  • 3D Builder

  • Azure App Service

  • Azure Data Box Gateway

  • Azure DevOps

  • Azure Machine Learning

  • HoloLens

  • Internet Storage Name Service

  • Microsoft Defender for Endpoint

  • Microsoft Defender for IoT

  • Microsoft Dynamics

  • Microsoft Edge (Chromium-based)

  • Microsoft Exchange Server

  • Microsoft Graphics Component

  • Microsoft Office

  • Microsoft Office OneNote

  • Microsoft Office Publisher

  • Microsoft Office SharePoint

  • Microsoft Office Word

  • Microsoft PostScript Printer Driver

  • Microsoft WDAC OLE DB provider for SQL

  • Microsoft Windows Codecs Library

  • Power BI

  • SQL Server

  • Visual Studio

  • Windows Active Directory

  • Windows ALPC

  • Windows Common Log File System Driver

  • Windows Cryptographic Services

  • Windows Distributed File System (DFS)

  • Windows Fax and Scan Service

  • Windows HTTP.sys

  • Windows Installer

  • Windows iSCSI

  • Windows Kerberos

  • Windows MSHTML Platform

  • Windows ODBC Driver

  • Windows Protected EAP (PEAP)

  • Windows SChannel

  • Windows Win32K

 Learn more in the MSRC’s release notes.

Three zero-day vulnerabilities patched  

 February’s Patch Tuesday comes with updates for three zero-day vulnerabilities.

  • CVE-2023-21823 – Windows Graphics Component Remote Code Execution Vulnerability

As per Microsoft, "An attacker who successfully exploited this vulnerability could gain SYSTEM privileges."

Since the security update will be pushed out to users via the Microsoft Store rather than Windows Update, customers who have disabled the automatic updates in the Microsoft Store won't be receiving the update automatically.

While the vulnerability is being actively exploited, it hasn't been publicly disclosed yet.

  •  CVE-2023-21715 – Microsoft Publisher Security Features Bypass Vulnerability  

As per Microsoft, "An attacker who successfully exploited this vulnerability could gain SYSTEM privileges."

This zero-day in Microsoft Publisher allows a specially crafted document to bypass Office macro policies that block untrusted or malicious files. Once the flaw is exploited, macros in the malicious Publisher document would run without first warning the user.

Further, Microsoft has also explained that the attack can be carried out locally by a user that has authentication to the targeted system. On the other hand, unauthenticated attackers (users) could lure in the victims through social engineering attacks.

While the vulnerability is being actively exploited, it hasn't been publicly disclosed yet.

  •  CVE-2023-23376 – Windows Common Log File System Driver Elevation of Privilege Vulnerability

Speaking of this actively exploited zero-day vulnerability, Microsoft explains, "An attacker who successfully exploited this vulnerability could gain SYSTEM privileges."

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

Third-party vendors such as Apple, Atlassian, Adobe, Cisco, Google, Fortra and SAP released updates in February 2023.

Best practices to handle patch management in a hybrid work environment  

Most organizations have opted to embrace remote work even after they have been cleared to return to the office. 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 or Patch 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!