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Microsoft releases Windows 10 KB5075912 extended security update

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Microsoft has continued to issue extended security updates for Windows 10, addressing critical vulnerabilities and platform stability issues. The May 2026 KB5087544 update fixes Patch Tuesday vulnerabilities, resolves Remote Desktop security warning rendering problems in multi-monitor environments, and advances Secure Boot certificate deployment through improved device targeting and reporting. The update raises Windows 10 to build 19045.7291 (Enterprise LTSC 2021 to 19044.7291) and introduces a Daylight Saving Time adjustment for Egypt. Earlier, Microsoft released KB5075912 in February 2026 to remediate six zero-day vulnerabilities and continue replacing expiring Secure Boot certificates. That update addressed shutdown/hibernation failures when System Guard Secure Launch was enabled, incorporated Chinese font changes for GB18030-2022A compliance, and resolved stability issues affecting certain GPU configurations. Microsoft has emphasized a controlled, phased rollout of Secure Boot certificate replacements to mitigate bypass risks from expiring certificates. The updates remain available to Windows 10 Enterprise LTSC users and ESU program participants.

Timeline

  1. 10.02.2026 21:06 2 articles · 3mo ago

    Microsoft releases Windows 10 KB5075912 extended security update

    Microsoft has released the Windows 10 KB5075912 extended security update to fix February 2026 Patch Tuesday vulnerabilities, including six zero-days, and to continue rolling out replacements for expiring Secure Boot certificates. The update addresses several known issues, including a problem preventing devices from shutting down or hibernating if System Guard Secure Launch is enabled. It also includes changes to Chinese fonts and GPU stability fixes. This article clarifies that the broader Windows 10 extended security update program continues with the May 2026 KB5087544 release, which addresses additional Patch Tuesday vulnerabilities, corrects Remote Desktop security warning rendering issues in multi-monitor configurations, improves Secure Boot state reporting and targeted certificate deployment, and includes a Daylight Saving Time adjustment for Egypt. A known issue involving BitLocker recovery key prompts under specific TPM Group Policy configurations is also documented.

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