Welcome to 2026. Let's see what Microsoft has in store for us this year. Our first Patch Tuesday of the year gives us 3 zero days to deal with. Today, Microsoft released 114 updates and in the last 30 days a long list of 227 additional updates for a total of 341 updates in the past 30 days. That's 30 more updates for this month than we had in lasts months newsletter. Now keep in mind that a very large number of the 227 additional updates are related to open source software in the chart below.

So let's dive in to the three zero-day vulnerabilities.

Our first zero day is CVE-2026-20805. This information disclosure is currently being exploited but not publicly disclosed. This vulnerability could allow an unauthorized actor to disclose local information in Desktop Windows Manager. The fix for this vulnerability was released today and rated "Important" by Microsoft.

Next is CVE-2026-21265. This security feature bypass is publicly disclosed but exploitation has not been detected at this time. An attacker who is successful could bypass a systems secure boot process. A systems certificates related to UEFI KEK and DB which are reaching expiration could allow the system to be vulnerable. You can click on the CVE link to see which certificates are suspect.

Our third and final zero day is CVE-2023-31096. Don't let the 2023 fool you. This update was released today. This elevation of privilege affects 3rd party Agere Soft Modem drivers that ship natively on all currently supported OS's. Both driver files, agrsm64.sys and agrsm.sys, are being removed in this update. If you currently have any soft modem's using these drivers, be aware that they will no longer work after the update is applied.

So, welcome to 2026. Another year and here we go again. Be sure to check out the chart below to see if any of the affected products are in your environment. Besides that it is a pretty normal month. Below the chart you will find a long list of Azure Linux and CBL Mariner products and versions. I didn't want to "clog up" the chart with all that data so I put it below the chart. See you next month!

So, without further ado, here’s the chart of MS patches that affect Windows platforms in the past month.

I didn't want to overflow the chart with the products and versions in this month's release for "Open Source Software". Below is a list of products and versions included:

Azure Linux:
azl3 avahi 0.8-5, azl3 coredns 1.11.4-11, azl3 edk2 20240524git3e722403cd16-10, azl3 fluent-bit 3.1.10-2, azl3 glib 2.78.6-5, azl3 gnupg2 2.4.7-1, azl3 hdf5 1.14.6-1, azl3 httpd 2.4.65-1, azl3 javapackages-bootstrap 1.14.0-3, azl3 jq 1.7.1-4, azl3 kata-containers 3.19.1.kata2-2, azl3 kata-containers-cc 3.15.0.aks0-5, azl3 keda 2.14.1-7, azl3 kernel 6.6.117.1-1, azl3 kernel 6.6.119.3-1, azl3 kubernetes 1.30.10-16, azl3 libcap 2.69-10, azl3 libpcap 1.10.5-1, azl3 libsodium 1.0.19-1, azl3 libsoup 3.4.4-10, azl3 libtpms 0.9.6-8, azl3 mariadb 10.11.11-1, azl3 net-snmp 5.9.4-1, azl3 nmap 7.95-2, azl3 php 8.3.23-1, azl3 python-filelock 3.14.0-1, azl3 python-tensorboard 2.16.2-6, azl3 pytorch 2.2.2-9, azl3 qemu 8.2.0-25, azl3 rpm-ostree 2024.4-5, azl3 ruby 3.3.5-6, azl3 rubygem-elasticsearch 8.9.0-1, azl3 rust 1.75.0-22, azl3 rust 1.86.0-10, azl3 util-linux 2.40.2-1

CBL Mariner:
cbl2 avahi 0.8-4, cbl2 coredns 1.11.1-24, cbl2 edk2 20230301gitf80f052277c8-43, cbl2 glib 2.71.0-8, cbl2 glib 2.71.0-9, cbl2 gnupg2 2.4.0-2, cbl2 hdf5 1.14.6-1, cbl2 httpd 2.4.65-1, cbl2 hvloader 1.0.1-14, cbl2 jq 1.6-5, cbl2 kata-containers 3.2.0.azl2-7, cbl2 kata-containers-cc 3.2.0.azl2-8, cbl2 keda 2.4.0-30, cbl2 kernel 5.15.186.1-1, cbl2 kubernetes 1.28.4-19, cbl2 kubernetes 1.28.4-21, cbl2 libpcap 1.10.1-4, cbl2 libsodium 1.0.18-6, cbl2 libsoup 3.0.4-10, cbl2 mariadb 10.6.21-1, cbl2 mariadb 10.6.24-1, cbl2 net-snmp 5.9.4-1, cbl2 nmap 7.93-3, cbl2 php 8.1.33-1, cbl2 python-tensorboard 2.11.0-3, cbl2 pytorch 2.0.0-11, cbl2 qemu 6.2.0-26, cbl2 reaper 3.1.1-22, cbl2 rpm-ostree 2022.1-7, cbl2 ruby 3.1.7-3, cbl2 rubygem-elasticsearch 8.3.0-1, cbl2 rust 1.72.0-11, cbl2 util-linux 2.37.4-10, cbl2 util-linux 2.37.4-9