KB5120418: Windows Server 2019 Security Update (August 2026)

Full tracking and change history for KB5120418

Released

2026-08-11

Last changed

2026-08-11

Changes tracked

2

Senserva began recording day-to-day change history on 2026-07-07, and refreshes it several times a day. Release dates are historical where Microsoft publishes them; revision history is tracked from that date forward, so it does not include changes made before then.

Check if KB5120418 is installed

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Known issues, from Microsoft

Quoted from Microsoft's support article for KB5120418 (checked 2026-08-11). Verify against the article before acting.

Microsoft is not currently aware of any issues with this update.

Applies to: Windows 10 Enterprise LTSB 2016 and Windows 10 IoT Enterprise 2016 LTSB

This security update includes fixes and improvements that are a part of the following update:

July 14, 2026—KB5099535 (OS Build 14393.9339)

The following is a summary of the issues that this update addresses. The bold text within the brackets indicates the item or area of the change we are documenting.

[Backup] File History automatic backups to network shares using Server Message Block (SMB) might fail with an incorrect "invalid credentials" error. When this issue occurs, scheduled backups do not copy any files. This update resolves the issue.

[Secure Boot] This update includes additional high confidence device targeting data, increasing coverage of devices eligible to automatically receive new Secure Boot certificates. Certificate deployment via Windows updates continues across supported PCs and non-managed business devices in the coming months.

If you installed earlier updates, only the new updates contained in this package will be downloaded and installed on your device.

For more information about security vulnerabilities, see the Security Update Guide website and the August 2026 Security Updates .

For more information about Windows 10, version 1607, see its update history page .

For information about Windows update ...

CVEs fixed by this update

Sorted exploited-first, then by CVSS. Every CVE links to its Senserva page with the full risk facts, references, and a ready-to-paste AI prompt.

What the press says about this update

Trusted-source coverage of the CVEs this update fixes, pulled live from their own feeds.

Scope and sources

Affected products

• Windows 10 Version 1809 for 32-bit Systems
• Windows 10 Version 1809 for x64-based Systems
• Windows Server 2019

Also released in August 2026

KB5002882

39 CVEs · Critical · exploited

KB5002883

40 CVEs · Critical · exploited

KB5002891

40 CVEs · Critical · exploited

KB5120228

212 CVEs · Critical · exploited

KB5120229

194 CVEs · Critical · exploited

KB5120233

213 CVEs · Critical · exploited

KB5120238

181 CVEs · Critical · exploited

KB5120240

170 CVEs · Critical · exploited

The full month, summarized: Microsoft Patch Tuesday.

Authoritative references

Official KB5120418 page (Microsoft Support)Microsoft Update CatalogMicrosoft Security Update Guide