Microsoft releases Windows 10 KB5122878 extended security update
Microsoft released the Windows 10 KB5122878 extended security update as part of the September 2026 Patch Tuesday. This update includes security fixes addressing a record 966 vulnerabilities across Microsoft products, including two zero-day exploits that were actively exploited. It also contains bug fixes and improvements such as enhanced Secure Boot certificate deployment, time zone adjustment for Morocco, improved logging for OMA DM Client, and fixes for Remote Desktop audio redirection and BitLocker Group Policy issues. No new features are included, and Microsoft reports no known issues with this update.
AI Analysis
Technical Summary
The Windows 10 KB5122878 update is an extended security update primarily delivering September 2026 Patch Tuesday fixes, which cover 966 vulnerabilities including two zero-day flaws actively exploited in the wild. It updates Windows 10 Enterprise LTSC and ESU-enrolled systems to build 19045.7725 or 19044.7725 respectively. The update enhances Secure Boot certificate targeting, adjusts Morocco Standard Time to UTC+00:00, improves OMA DM Client logging, updates Windows Code Integrity policies for certificate authority rotation, fixes Remote Desktop audio redirection issues, and addresses BitLocker Group Policy recovery key prompts. Microsoft states there are no known issues with this update.
Potential Impact
This update addresses a large number of security vulnerabilities, including two zero-day exploits actively used by attackers, thereby reducing the risk of compromise on affected Windows 10 systems. It also fixes functional issues impacting Remote Desktop audio and BitLocker recovery key prompts. Applying this update improves system security posture and stability. No new features are introduced, and no known issues have been reported by Microsoft.
Mitigation Recommendations
A security update is available and should be installed by Windows 10 Enterprise LTSC users and those enrolled in the Extended Security Update (ESU) program. The update can be obtained via Windows Update by manually checking for updates. Microsoft reports no known issues with this update, so applying it is recommended to mitigate the addressed vulnerabilities and bugs.
Microsoft releases Windows 10 KB5122878 extended security update
Description
Microsoft released the Windows 10 KB5122878 extended security update as part of the September 2026 Patch Tuesday. This update includes security fixes addressing a record 966 vulnerabilities across Microsoft products, including two zero-day exploits that were actively exploited. It also contains bug fixes and improvements such as enhanced Secure Boot certificate deployment, time zone adjustment for Morocco, improved logging for OMA DM Client, and fixes for Remote Desktop audio redirection and BitLocker Group Policy issues. No new features are included, and Microsoft reports no known issues with this update.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Windows 10 KB5122878 update is an extended security update primarily delivering September 2026 Patch Tuesday fixes, which cover 966 vulnerabilities including two zero-day flaws actively exploited in the wild. It updates Windows 10 Enterprise LTSC and ESU-enrolled systems to build 19045.7725 or 19044.7725 respectively. The update enhances Secure Boot certificate targeting, adjusts Morocco Standard Time to UTC+00:00, improves OMA DM Client logging, updates Windows Code Integrity policies for certificate authority rotation, fixes Remote Desktop audio redirection issues, and addresses BitLocker Group Policy recovery key prompts. Microsoft states there are no known issues with this update.
Potential Impact
This update addresses a large number of security vulnerabilities, including two zero-day exploits actively used by attackers, thereby reducing the risk of compromise on affected Windows 10 systems. It also fixes functional issues impacting Remote Desktop audio and BitLocker recovery key prompts. Applying this update improves system security posture and stability. No new features are introduced, and no known issues have been reported by Microsoft.
Mitigation Recommendations
A security update is available and should be installed by Windows 10 Enterprise LTSC users and those enrolled in the Extended Security Update (ESU) program. The update can be obtained via Windows Update by manually checking for updates. Microsoft reports no known issues with this update, so applying it is recommended to mitigate the addressed vulnerabilities and bugs.
Technical Details
- Classification
- {"confidence":0.88,"severitySource":"default","classifier":"rss-v2"}
- Article Source
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Threat ID: 6aa05ce4acd9273b4917d25a
Added to database: 09/08/2026, 19:07:16 UTC
Last enriched: 09/08/2026, 19:07:22 UTC
Last updated: 09/08/2026, 20:01:46 UTC
Views: 5
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