kb5125758

KB5125758 is a Safe OS Dynamic Update for Windows 11 versions 24H2 and 25H2 that refreshes the Windows Recovery Environment (WinRE) to version 10.0.26100.9545. Released by Microsoft on September 22, 2026, it replaces KB5124015, installs automatically through Windows Update, requires no restart, and cannot be removed. Microsoft's release note says only that it makes improvements to WinRE without listing specific fixes. For most PCs nothing needs to be done, but administrators will care about where the package is published, how to confirm it reached the recovery image, and how it differs from the Secure Boot certificate deadline noted on the same support page.