KB5126045: Overview with user sentiment and feedback
Last Updated October 29, 2026
Probability of successful installation and continued operation of the machine
Overview
KB5126045 is the September 8, 2026 Security and Quality Rollup for .NET Framework 4.6.2, 4.7, 4.7.1, and 4.7.2 on Windows Server 2012 R2. It is an Extended Security Update (ESU) release, since Windows Server 2012 R2 is past end of support and ESUs run until October 13, 2026. It replaces KB5121649 and KB5102205.
General Purpose
- Fixes CVE-2026-62886, a .NET Framework elevation of privilege vulnerability.
- Fixes CVE-2026-69522, a .NET Framework remote code execution vulnerability.
- No new quality or reliability fixes are listed.
- Recommends installing the latest servicing stack update (KB5044411) first.
- Installing on Azure Arc-enabled servers may fail unless ESU network endpoint requirements are met.
General Sentiment
Community discussion on this specific KB is minimal, so no substantive user reception was found. The update is security-focused and Microsoft states no known issues. Its main friction point is the Azure Arc installation caveat.
Known Issues
Disclaimer: We take measures to ensure that AI-generated content is of the highest possible quality, but we cannot guarantee its accuracy and recommend that users do their own independent research. Generated on 2026-10-29 02:13 AM
