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 4 of 20 · sorted by risk, then score
Normal cycle60 on this page · tap one for its risk review
- Normal cycleWindowsOctober 13, 2026
CVE-2026-83869Windows Domain Name Service
Remote Code Execution · Severity Important · CVSS 9.8
In Windows Domain Name Service, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-83910RPC Runtime Library
Remote Code Execution · Severity Important · CVSS 9.8
In RPC Runtime Library, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-83935Microsoft XML
Remote Code Execution · Severity Important · CVSS 9.8
In Microsoft XML, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-84015Remote Access Point-to-Point Protocol (PPP) EAP-TLS
Remote Code Execution · Severity Important · CVSS 9.8
In Remote Access Point-to-Point Protocol (PPP) EAP-TLS, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-85792Windows Routing and Remote Access Service (RRAS)
Remote Code Execution · Severity Important · CVSS 9.8
In Windows Routing and Remote Access Service (RRAS), an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-85806Network Policy Server (NPS)
Remote Code Execution · Severity Important · CVSS 9.8
In Network Policy Server (NPS), an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-85809Windows Routing and Remote Access Service (RRAS)
Remote Code Execution · Severity Important · CVSS 9.8
In Windows Routing and Remote Access Service (RRAS), an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-85814Microsoft Windows Media Foundation
Remote Code Execution · Severity Important · CVSS 9.8
In Microsoft Windows Media Foundation, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-85928Windows Volume Manager Extension Driver
Remote Code Execution · Severity Important · CVSS 9.8
In Windows Volume Manager Extension Driver, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-88102Microsoft Failover Cluster
Remote Code Execution · Severity Important · CVSS 9.8
In Microsoft Failover Cluster, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126655) for 6 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-96096Windows Media Player
Remote Code Execution · Severity Important · CVSS 9.8
In Windows Media Player, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-96113Windows Domain Name Service
Remote Code Execution · Severity Important · CVSS 9.8
In Windows Domain Name Service, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126655) for 16 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-96219Windows Local Security Authority Subsystem Service (LSASS)
Remote Code Execution · Severity Important · CVSS 9.8
In Windows Local Security Authority Subsystem Service (LSASS), an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 24 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-96320Windows DHCP Server
Remote Code Execution · Severity Important · CVSS 9.8
In Windows DHCP Server, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126655) for 16 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-96864Microsoft Failover Cluster Virtual Driver
Remote Code Execution · Severity Important · CVSS 9.8
In Microsoft Failover Cluster Virtual Driver, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. 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.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-96909Windows BitLocker
Remote Code Execution · Severity Important · CVSS 9.8
In Windows BitLocker, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126653, KB5126655) for 14 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-96924Windows OLE
Remote Code Execution · Severity Important · CVSS 9.8
In Windows OLE, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-97805Windows Partition Management Driver
Remote Code Execution · Severity Important · CVSS 9.8
In Windows Partition Management Driver, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-97815Windows Error Reporting
Remote Code Execution · Severity Important · CVSS 9.8
In Windows Error Reporting, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-97816Microsoft OpenSSH for Windows
Remote Code Execution · Severity Important · CVSS 9.8
In Microsoft OpenSSH for Windows, an attacker with no account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 24 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-96252Active Directory Federation Services (AD FS)
Spoofing · Severity Important · CVSS 9.1
In Active Directory Federation Services (AD FS), an attacker with no account could impersonate a trusted user, site or file over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.1. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126655) for 16 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-105008Windows Schannel
Spoofing · Severity Important · CVSS 9
In Windows Schannel, an attacker with no account could impersonate a trusted user, site or file over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.0. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-85818Windows Schannel
Spoofing · Severity Important · CVSS 9
In Windows Schannel, an attacker with no account could impersonate a trusted user, site or file over the network without anyone clicking anything. Microsoft severity Important, CVSS 9.0. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646, KB5126653, KB5126655) for 14 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-102203RPC Runtime
Remote Code Execution · Severity Important · CVSS 8.8
In RPC Runtime, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-103575Remote Desktop Client
Remote Code Execution · Severity Important · CVSS 8.8
In Remote Desktop Client, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. 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.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-105007Windows NDIS
Elevation of Privilege · Severity Important · CVSS 8.8
In Windows NDIS, an attacker with no account could take higher privileges over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-108458Remote Desktop Client
Remote Code Execution · Severity Important · CVSS 8.8
In Remote Desktop Client, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. 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.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-108463Windows SmartScreen
Security Feature Bypass · Severity Important · CVSS 8.8
In Windows SmartScreen, an attacker with no account could get around a Windows security protection over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5127646, KB5127648) for 8 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 6, 2026
CVE-2026-69266Windows DHCP Server
Remote Code Execution · Severity Important · CVSS 8.8 · Fixed earlier (September 2026)
In Windows DHCP Server, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Microsoft disclosed it on October 6, 2026, but the fix had already shipped in the September 2026 Windows security update (KB5122871, KB5122876, KB5122882) for 16 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-69326Graphic Fonts
Remote Code Execution · Severity Important · CVSS 8.8
In Graphic Fonts, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 14, 2026
CVE-2026-69334Windows Volume Manager Extension Driver
Remote Code Execution · Severity Important · CVSS 8.8 · Fixed earlier (September 2026)
In Windows Volume Manager Extension Driver, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Microsoft disclosed it on October 14, 2026, but the fix had already shipped in the September 2026 Windows security update (KB5122871, KB5122876, KB5122878) for 30 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-69521Windows iSCSI
Remote Code Execution · Severity Important · CVSS 8.8
In Windows iSCSI, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5122871, KB5122876, KB5122878) for 30 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 7, 2026
CVE-2026-69598Windows iSCSI
Remote Code Execution · Severity Important · CVSS 8.8 · Fixed earlier (September 2026)
In Windows iSCSI, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation unlikely". Microsoft disclosed it on October 7, 2026, but the fix had already shipped in the September 2026 Windows security update (KB5122871, KB5122876, KB5122878) for 30 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-69765Windows Storport Miniport Driver
Remote Code Execution · Severity Important · CVSS 8.8
In Windows Storport Miniport Driver, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation unlikely". Fixed in the October 2026 Windows security update (KB5126646) for 2 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-69945Windows AppX Deployment Extensions
Elevation of Privilege · Severity Important · CVSS 8.8
In Windows AppX Deployment Extensions, an attacker with an ordinary user account could take higher privileges once they can run code on the PC. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126653, KB5126655) for 20 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-69985Windows libarchive
Remote Code Execution · Severity Important · CVSS 8.8
In Windows libarchive, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. 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.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-70068Windows Client-Side Caching (CSC) Service
Elevation of Privilege · Severity Important · CVSS 8.8
In Windows Client-Side Caching (CSC) Service, an attacker with no account could take higher privileges over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-70069Windows DHCP Server
Remote Code Execution · Severity Important · CVSS 8.8
In Windows DHCP Server, an attacker with an ordinary user account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126655) for 16 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-70089Windows GDI
Remote Code Execution · Severity Important · CVSS 8.8
In Windows GDI, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-70149Windows Client Side Caching driver (csc.sys)
Elevation of Privilege · Severity Important · CVSS 8.8
In Windows Client Side Caching driver (csc.sys), an attacker with no account could take higher privileges over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-70158Windows Routing and Remote Access Service (RRAS)
Remote Code Execution · Severity Important · CVSS 8.8
In Windows Routing and Remote Access Service (RRAS), an attacker with an ordinary user account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 8.8. 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.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-70167Windows Domain Name Service
Remote Code Execution · Severity Important · CVSS 8.8
In Windows Domain Name Service, an attacker with an ordinary user account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126655) for 4 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-70185Microsoft PowerShell
Security Feature Bypass · Severity Important · CVSS 8.8
In Microsoft PowerShell, an attacker with an ordinary user account could get around a Windows security protection once they can run code on the PC. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-70210Windows OLE DB
Elevation of Privilege · Severity Important · CVSS 8.8
In Windows OLE DB, an attacker with no account could take higher privileges over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-70258Microsoft Windows Media Foundation
Remote Code Execution · Severity Important · CVSS 8.8
In Microsoft Windows Media Foundation, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. 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.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-70262WebDAV
Elevation of Privilege · Severity Important · CVSS 8.8
In WebDAV, an attacker with no account could take higher privileges over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-70275Windows CD-ROM File System Driver
Remote Code Execution · Severity Important · CVSS 8.8
In Windows CD-ROM File System Driver, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. 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.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-70299Windows Bind Filter Driver
Elevation of Privilege · Severity Important · CVSS 8.8
In Windows Bind Filter Driver, an attacker with an ordinary user account could take higher privileges once they can run code on the PC. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126653) for 4 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-70580Windows Credential Guard
Spoofing · Severity Important · CVSS 8.8
In Windows Credential Guard, an attacker with an ordinary user account could impersonate a trusted user, site or file once they can run code on the PC. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 24 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-77496Windows Imaging Component
Remote Code Execution · Severity Important · CVSS 8.8
In Windows Imaging Component, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-83523Windows Image Acquisition
Remote Code Execution · Severity Important · CVSS 8.8
In Windows Image Acquisition, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5127646, KB5127648) for 10 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-83642Windows Domain Name Service
Remote Code Execution · Severity Important · CVSS 8.8
In Windows Domain Name Service, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. 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.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-83643Windows Error Reporting
Remote Code Execution · Severity Important · CVSS 8.8
In Windows Error Reporting, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. 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.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-83688Remote Desktop Client
Remote Code Execution · Severity Important · CVSS 8.8
In Remote Desktop Client, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-83716Windows Hyper-V
Remote Code Execution · Severity Important · CVSS 8.8
In Windows Hyper-V, an attacker with an ordinary user account could run their own code once they can run code on the PC. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 28 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-83725Microsoft Windows Search Component
Remote Code Execution · Severity Important · CVSS 8.8
In Microsoft Windows Search Component, an attacker with no account could run their own code over the network, but only if someone opens a file, link or message. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 32 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-83728Windows Hyper-V
Spoofing · Severity Important · CVSS 8.8
In Windows Hyper-V, an attacker with an ordinary user account could impersonate a trusted user, site or file once they can run code on the PC. Microsoft severity Important, CVSS 8.8. 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.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-83759Windows Encrypting File System (EFS)
Remote Code Execution · Severity Important · CVSS 8.8
In Windows Encrypting File System (EFS), an attacker with an ordinary user account could run their own code over the network without anyone clicking anything. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126651, KB5126653) for 28 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-83771Windows Camera Frame Server Monitor
Elevation of Privilege · Severity Important · CVSS 8.8
In Windows Camera Frame Server Monitor, an attacker with no account could take higher privileges from the same local network without anyone clicking anything. Microsoft severity Important, CVSS 8.8. Microsoft rates it "exploitation less likely". Fixed in the October 2026 Windows security update (KB5126646, KB5126653, KB5126655) for 14 supported Windows versions; a restart is required.
- Normal cycleWindowsOctober 13, 2026
CVE-2026-83777Windows Bluetooth Service
Elevation of Privilege · Severity Important · CVSS 8.8
In Windows Bluetooth Service, an attacker with no account could take higher privileges from the same local network without anyone clicking anything. Microsoft severity Important, CVSS 8.8. 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.
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.