April 2023 Patch Tuesday comes with fixes for 97 vulnerabilities, including 1 zero day

Keeping the trend intact, April 2023’s Patch Tuesday lists fixes for 97 vulnerabilities, including one zero day and seven critical vulnerabilities. With the zero-day vulnerability 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.

April 2023 Patch Tuesday: Security updates lineup  

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

  • .NET Core

  • Azure Machine Learning

  • Azure Service Connector

  • Microsoft Bluetooth Driver

  • Microsoft Defender for Endpoint

  • Microsoft Dynamics

  • Microsoft Dynamics 365 Customer Voice

  • Microsoft Edge (Chromium-based)

  • Microsoft Graphics Component

  • Microsoft Message Queuing

  • Microsoft Office

  • Microsoft Office Publisher

  • Microsoft Office SharePoint

  • Microsoft Office Word

  • Microsoft PostScript Printer Driver

  • Microsoft Printer Drivers

  • Microsoft WDAC OLE DB provider for SQL

  • Microsoft Windows DNS

  • Visual Studio

  • Visual Studio Code

  • Windows Active Directory

  • Windows ALPC

  • Windows Ancillary Function Driver for WinSock

  • Windows Boot Manager

  • Windows Clip Service

  • Windows CNG Key Isolation Service

  • Windows Common Log File System Driver

  • Windows DHCP Server

  • Windows Enroll Engine

  • Windows Error Reporting

  • Windows Group Policy

  • Windows Internet Key Exchange (IKE) Protocol

  • Windows Kerberos

  • Windows Kernel

  • Windows Layer 2 Tunneling Protocol

  • Windows Lock Screen

  • Windows Netlogon

  • Windows Network Address Translation (NAT)

  • Windows Network File System

  • Windows Network Load Balancing

  • Windows NTLM

  • Windows PGM

  • Windows Point-to-Point Protocol over Ethernet (PPPoE)

  • Windows Point-to-Point Tunneling Protocol

  • Windows Raw Image Extension

  • Windows RDP Client

  • Windows Registry

  • Windows RPC API

  • Windows Secure Boot

  • Windows Secure Channel

  • Windows Secure Socket Tunneling Protocol (SSTP)

  • Windows Transport Security Layer (TLS)

  • Windows Win32K

Learn more in the MSRC’s release notes.

One zero-day vulnerability patched  

April’s Patch Tuesday comes with an update for an actively exploited zero-day vulnerability.

  • CVE-2023-28252 - Windows Common Log File System Driver Elevation of Privilege Vulnerability

This elevation of privilege vulnerability in the Windows Common Log File System Driver has been assigned a CVSS v3.1 score of 7.8 (base score metrics) and is being actively exploited.

Microsoft's advisory states, "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 Google, Apple, Cisco, and SAP released updates in April 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!