Windows 10 KB5099539 Extended Security Update Released

Wed, 15 Jul 2026 12:11:39 +0000

Engineer — Plan: Windows 10 is in ESU territory; if you still run Win10 endpoints or golden images, deploy KB5099539 to stay covered under the extended support contract — schedule within your normal patch window.
SOC/IR — Skip
Leader — Plan: If your organization is paying for Windows 10 ESU, confirm KB5099539 is being deployed; if not, this is a prompt to assess Win10 fleet size and budget for ESU licensing or migration costs before end-of-extended-support.

Esu on CuraSec