Windows 10 KB5120249 cumulative update released with fixes
Microsoft released the Windows 10 KB5120249 cumulative update for versions 22H2 and 21H2 as part of the August 2026 Patch Tuesday. The update addresses security vulnerabilities and bugs, including a fix for File History backup failures to network shares due to invalid credentials and expands the rollout of new Secure Boot certificates. This update is mandatory and improves device security by increasing coverage for Secure Boot certificate deployment. No new issues have been reported with this update so far.
AI Analysis
Technical Summary
The Windows 10 KB5120249 cumulative update fixes security vulnerabilities and bugs in versions 22H2 and 21H2. It resolves a File History backup issue where automatic backups to network shares using SMB could fail with an 'invalid credentials' error, preventing scheduled backups from copying files. Additionally, the update expands the rollout of new Secure Boot certificates by including more high confidence device targeting data, enhancing device security. This update corresponds to OS Builds 19045.7663 and 19044.7663 and is part of the August 2026 Patch Tuesday security updates.
Potential Impact
The update addresses security vulnerabilities that could affect system integrity and backup reliability. Fixing the File History backup issue ensures scheduled backups function correctly, preventing potential data loss. Expanding Secure Boot certificate deployment enhances device security by improving the trustworthiness of the boot process. No new issues have been reported with this update, indicating a stable release.
Mitigation Recommendations
Install the Windows 10 KB5120249 cumulative update via Windows Update or manually from the Microsoft Update Catalog. This update is mandatory as it contains critical security fixes. No additional mitigation actions are required beyond applying this update.
Windows 10 KB5120249 cumulative update released with fixes
Description
Microsoft released the Windows 10 KB5120249 cumulative update for versions 22H2 and 21H2 as part of the August 2026 Patch Tuesday. The update addresses security vulnerabilities and bugs, including a fix for File History backup failures to network shares due to invalid credentials and expands the rollout of new Secure Boot certificates. This update is mandatory and improves device security by increasing coverage for Secure Boot certificate deployment. No new issues have been reported with this update so far.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Windows 10 KB5120249 cumulative update fixes security vulnerabilities and bugs in versions 22H2 and 21H2. It resolves a File History backup issue where automatic backups to network shares using SMB could fail with an 'invalid credentials' error, preventing scheduled backups from copying files. Additionally, the update expands the rollout of new Secure Boot certificates by including more high confidence device targeting data, enhancing device security. This update corresponds to OS Builds 19045.7663 and 19044.7663 and is part of the August 2026 Patch Tuesday security updates.
Potential Impact
The update addresses security vulnerabilities that could affect system integrity and backup reliability. Fixing the File History backup issue ensures scheduled backups function correctly, preventing potential data loss. Expanding Secure Boot certificate deployment enhances device security by improving the trustworthiness of the boot process. No new issues have been reported with this update, indicating a stable release.
Defensive Guidance
Install the Windows 10 KB5120249 cumulative update via Windows Update or manually from the Microsoft Update Catalog. This update is mandatory as it contains critical security fixes. No additional mitigation actions are required beyond applying this update.
Technical Details
- Classification
- {"confidence":0.3,"severitySource":"default","classifier":"rss-v2"}
Threat ID: 6a7b6948bf8831d5392ddb83
Added to database: 08/11/2026, 18:26:16 UTC
Last enriched: 08/11/2026, 18:26:26 UTC
Last updated: 08/12/2026, 02:41:37 UTC
Views: 10
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