Windows · Microsoft · released October 13, 2026
Windows security updates, October 2026: every vulnerability, rated
Microsoft published 1,165 Windows vulnerabilities in October 2026, most of them on Patch Tuesday, October 13, 2026. 42 are rated Critical. 2 were already being exploited, so they go to the top of the list. 158 more deserve attention this week; 1,005 can follow the normal monthly rollout. 51 were fixed by an earlier update and only disclosed this month, so a PC that is already current is covered. The updates that carry these fixes need a restart.
- CVEs
- 1,165
- Patch now
- 2
- This week
- 158
- Normal cycle
- 972
- Low
- 33
Fixed in: October 2026 Windows security update restart requiredMicrosoft release notes
Page 20 of 20 · sorted by risk, then score
Low25 on this page · tap one for its risk review
- LowWindowsOctober 13, 2026
CVE-2026-70074Windows DNS
Information Disclosure · Severity Important · CVSS 5.5
In Windows DNS, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126655) for 16 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-70090Windows Netlogon
Information Disclosure · Severity Important · CVSS 5.5
In Windows Netlogon, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-70141Microsoft Windows Search Component
Information Disclosure · Severity Important · CVSS 5.5
In Microsoft Windows Search Component, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-83507Windows Update Orchestrator Service
Information Disclosure · Severity Important · CVSS 5.5
In Windows Update Orchestrator Service, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126653, KB5126655) for 20 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-83565Windows Encrypting File System (EFS)
Information Disclosure · Severity Important · CVSS 5.5
In Windows Encrypting File System (EFS), an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 28 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-83705HTTP.sys
Information Disclosure · Severity Important · CVSS 5.5
In HTTP.sys, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-83713Windows Universal Disk Format File System Driver (UDFS)
Information Disclosure · Severity Important · CVSS 5.5
In Windows Universal Disk Format File System Driver (UDFS), an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-83737Windows NTFS
Information Disclosure · Severity Important · CVSS 5.5
In Windows NTFS, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-83765Windows DWM Core Library
Information Disclosure · Severity Important · CVSS 5.5
In Windows DWM Core Library, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 30 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-83794Windows Portable Device MTP Driver
Information Disclosure · Severity Important · CVSS 5.5
In Windows Portable Device MTP Driver, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-83835Windows Common Log File System Driver
Information Disclosure · Severity Important · CVSS 5.5
In Windows Common Log File System Driver, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-83875Windows Human Interface Device
Information Disclosure · Severity Important · CVSS 5.5
In Windows Human Interface Device, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 24 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-83887HID Parser Library
Information Disclosure · Severity Important · CVSS 5.5
In HID Parser Library, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 24 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-83907Windows Hello
Information Disclosure · Severity Important · CVSS 5.5
In Windows Hello, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126653, KB5126657, KB5127646) for 16 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-85831Windows Biometric Service
Information Disclosure · Severity Important · CVSS 5.5
In Windows Biometric Service, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 24 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-85857Windows Kernel-Mode Drivers
Information Disclosure · Severity Important · CVSS 5.5
In Windows Kernel-Mode Drivers, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-96860Windows USB Print Driver
Information Disclosure · Severity Important · CVSS 5.5
In Windows USB Print Driver, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-96910Microsoft Windows Search Component
Information Disclosure · Severity Important · CVSS 5.5
In Microsoft Windows Search Component, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 5.5. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-70025Windows Netlogon
Denial of Service · Severity Important · CVSS 5.3
In Windows Netlogon, an attacker with an ordinary user account could crash or stall the affected service over the network without anyone clicking anything. Microsoft severity Important, CVSS 5.3. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-102186Windows Network File System
Information Disclosure · Severity Important · CVSS 4.7
In Windows Network File System, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 4.7. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-69969Windows AppX Deployment Service
Information Disclosure · Severity Important · CVSS 4.7
In Windows AppX Deployment Service, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 4.7. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126653, KB5126655) for 20 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-83582Windows Graphics Kernel
Information Disclosure · Severity Important · CVSS 4.7
In Windows Graphics Kernel, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 4.7. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-83672Windows Installer
Information Disclosure · Severity Important · CVSS 4.7
In Windows Installer, an attacker with an ordinary user account could read information they shouldn't see once they can run code on the PC. Microsoft severity Important, CVSS 4.7. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-83788Windows rndismp6.sys
Information Disclosure · Severity Important · CVSS 4.6
In Windows rndismp6.sys, an attacker with no account could read information they shouldn't see with physical access to the device. Microsoft severity Important, CVSS 4.6. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- LowWindowsOctober 13, 2026
CVE-2026-88226Windows Storage Port Driver
Information Disclosure · Severity Important · CVSS 4.6
In Windows Storage Port Driver, an attacker with no account could read information they shouldn't see with physical access to the device. Microsoft severity Important, CVSS 4.6. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
Why an MSP manages this
Reading the list is the easy part
Nobody running a business reads all of them, and nobody should have to. The work is deciding which ones matter today, testing the fixes, getting them onto every PC and Mac without breaking the workday, and proving it was done.
- 01
Triage that starts with the exploited ones
Most of these fixes can ride the normal monthly rollout. A handful need action the same day. Telling them apart, every month, on every machine, is the core of the work, and it is the part an office manager rarely has time for.
- 02
Testing before everyone gets it
Updates go to a test ring and a pilot group first, so a broken accounting package or design tool shows up on two machines instead of forty, and the rollout pauses until it is sorted.
- 03
Restarts that don't wreck the workday
Windows updates usually need a restart and macOS updates often do. Deadlines, maintenance windows and grace periods get the fix installed without forcing a reboot in the middle of a client call.
- 04
Macs managed as seriously as PCs
Windows patching tools don't patch Macs. macOS updates need their own install-by deadlines through device management, and major upgrades need the same compatibility testing a Windows feature update gets.
- 05
A plan for machines that can't update
Hardware that ages out and versions past end of support stop getting every fix. They need a decision, isolate, upgrade or replace, before they become the easiest way in.
- 06
Proof when someone asks
Cyber insurance applications, customer security questionnaires and frameworks such as the FTC Safeguards Rule all ask how you keep systems patched. A managed service keeps the inventory and the reports that answer them.
The ins and outs
What keeping Windows and Mac patched actually involves
Windows
Patch Tuesday, and the exceptions
Microsoft ships security updates on the second Tuesday of each month, and out of band when something can't wait. This log marks the out-of-band ones.
Cumulative updates
Each month's Windows update carries the earlier months' fixes, so a PC that missed one catches up with the next, as long as it actually installs.
Fixed first, announced later
Some fixes ship before the vulnerability is disclosed. This log flags them, because a PC that is already current is already covered.
Rings, deferrals and deadlines
Windows Update for Business and Intune let you delay updates for a test group, set an install-by deadline and give a grace period before a forced restart.
Known Issue Rollback and safeguard holds
Microsoft can quietly roll back a change that breaks something, and holds back feature updates from PCs it knows will have trouble. Both explain why two PCs on the same network can be on different builds.
Feature updates and end of support
Each Windows version is serviced for a fixed period. Windows 10 PCs past end of support only get security fixes through the paid Extended Security Updates program.
Mac
No fixed release day
Apple publishes security updates when they are ready, often several times a month around a major release, so Mac patching runs on alerts, not a calendar.
Updates versus upgrades
A point update (26.7 to 26.7.1) fixes problems. A major upgrade (Tahoe to Golden Gate) changes the system and needs the same app testing as a Windows feature update.
Older versions get some fixes, not all
Apple's deployment guide says not every security issue is fixed in previous major versions. Staying a version behind is a choice with a cost, not a safe default.
Install-by deadlines through device management
Without enforcement, a macOS update prompt can be put off again and again. Device management can set a deadline so the update installs on schedule.
Macs that age out
When a Mac can no longer run a current macOS version, it stops getting the full set of fixes. Inventory by model and macOS version shows which ones are next.
Apple Business for zero-touch setup
New Macs enrolled through Apple Business arrive already managed, so update policy applies from the first login instead of after someone remembers to enroll them.
Both platforms
Third-party apps aren't on these lists
Browsers, PDF readers, accounting software, VPN clients and plug-ins patch on their own schedules. A machine can be current on Windows or macOS and still exposed through an app.
Firmware and drivers
BIOS and UEFI firmware, docks and network gear get security fixes too, and they rarely update themselves.
Recovery keys before big changes
Before a feature update or a major macOS upgrade, confirm BitLocker and FileVault recovery keys are escrowed somewhere you can reach.
Laptops that are rarely in the office
Remote and travelling staff need updates delivered over the internet with the same deadlines as office machines, or they drift months behind.
You can't patch what you can't see
An up-to-date inventory of every PC and Mac, with its version and last update, is what turns a list like this one into a finished job.