Find notable cyber news and cases, enriched with sources, timelines, and signals.
Home Browse News Feed Stats Watchlists Beta About Contact

Windows Server 2025 AD DS sync remediation

Advisory/Mitigation
First reported
Last updated
Happening score
H score 24
1 unique sources, 2 articles

Summary

Hide ▲

Microsoft issued a Known Issue Rollback Group Policy and registry workaround for a Windows Server 2025 directory-sync bug that can disrupt Microsoft Entra Connect Sync. The temporary mitigation matters because the flaw can leave large AD security groups only partially synchronized after KB5065426 or later updates. Administrators can apply the rollback policy on managed devices or the registry key on non-managed systems until the permanent fix reaches all customers.

Related Happenings

Microsoft Windows Update restricted-network download failure

Service Disruption
First: 19.05.2026 14:22 Last: 19.05.2026 14:22 Sources 1

About this happening: Microsoft's **Windows Update** is failing in **restricted network environments** after the **January 2026 optional non-security preview updates**, leaving affected systems unable...

Open Happening

Microsoft Windows 11 KB5089549 cumulative update

Security Patch Release
First: 18.05.2026 11:33 Last: 18.05.2026 11:33 Sources 1

About this happening: Microsoft's **KB5089549** **Windows 11** security update is failing to install on some systems, forcing affected devices to roll back during reboot. The problem is tied to a nearl...

Open Happening

Microsoft Windows Autopatch fix for EU restricted driver update deployment bug

Security Tool/Service
First: 13.05.2026 17:36 Last: 13.05.2026 17:36 Sources 1

About this happening: **Microsoft** fixed a **Windows Autopatch** service bug that let **restricted driver updates** reach some managed devices in the **EU**, bypassing admin approval controls and crea...

Open Happening

Microsoft May 2026 Patch Tuesday release

Security Patch Release
First: 13.05.2026 13:36 Last: 13.05.2026 13:36 Sources 1

About this happening: Microsoft's **May 13, 2026 Patch Tuesday** release fixed **138 vulnerabilities** across its product portfolio, including **Windows**, **Azure**, and **Edge**. None of the flaws we...

Open Happening

Microsoft security patch release for CVE-2023-43896

Security Patch Release
First: 04.05.2026 13:40 Last: 04.05.2026 13:40 Sources 1

About this happening: **Microsoft**'s **April 2026 Windows security updates** are blocking **psmounterex.sys**, which can break third-party backup apps on **Windows 10**, **Windows 11**, and **Windows...

Open Happening

Timeline

  1. 20.10.2025 18:27 1 articles · 7mo ago

    Microsoft acknowledges Windows Server 2025 AD DS sync bug

    Initial Disclosure

    Microsoft acknowledged a known issue affecting Windows Server 2025 systems that can leave Active Directory Domain Services (AD DS) synchronization and Microsoft Entra Connect Sync incomplete when large AD security groups exceed 10,000 members after the September 2025 Windows security update (KB5065426) or later updates.

    Show sources
    Open in new tab
  2. 20.10.2025 18:27 3 articles · 7mo ago

    Microsoft releases KIR workaround for Windows Server 2025 AD DS sync bug

    Mitigation Patch Update

    Microsoft made a Known Issue Rollback Group Policy available for impacted Windows devices and documented a registry override so administrators can reduce Microsoft Entra Connect Sync disruptions on Windows Server 2025 systems until the permanent fix reaches all customers next month's Patch Tuesday.

    Show sources
    Open in new tab