Ethical Hacking News
Microsoft has confirmed that some Windows domain controllers are experiencing a critical reboot loop issue after installing the April 2026 security updates. This known issue affects non-Global Catalog domain controllers in environments utilizing Privileged Access Management (PAM). Affected platforms include systems running Windows Server 2025, Windows Server 2022, Windows Server 23H2, Windows Server 2019, and Windows Server 2016. Microsoft has advised IT administrators to contact Microsoft Support for Business for mitigation measures and is working to address this issue through patches or updates.
Windows domain controllers experiencing reboot loops after installing April 2026 security updates. Affected non-Global Catalog (non-GC) domain controllers in environments with Privileged Access Management (PAM). Issue causes Local Security Authority Subsystem Service (LSASS) to crash, preventing authentication and directory services from functioning. Affected platforms include Windows Server 2025, 2022, 23H2, 2019, and 2016. Mitigation measures available through Microsoft Support for Business. Similar issues have been addressed in recent years by Microsoft, such as April 2025 and April 2024 security update issues.
Microsoft has recently confirmed that certain Windows domain controllers are experiencing a critical issue, where they enter reboot loops after installing the April 2026 security updates. This known issue affects non-Global Catalog (non-GC) domain controllers in environments that utilize Privileged Access Management (PAM), and is unlikely to affect personal devices managed by IT departments.
The problem arises when the Local Security Authority Subsystem Service (LSASS) crashes during startup, causing the domain controller to restart repeatedly. This prevents authentication and directory services from functioning, potentially rendering the domain unavailable. Affected platforms include systems running Windows Server 2025, Windows Server 2022, Windows Server 23H2, Windows Server 2019, and Windows Server 2016.
Microsoft has advised IT administrators to contact Microsoft Support for Business for mitigation measures that can be applied even after deploying the April 2026 update. This is a precautionary measure to prevent further disruptions in domain services.
This issue is not an isolated incident; Microsoft has previously addressed similar issues caused by security updates in recent years. In June 2025, it resolved Windows Server authentication problems caused by the April 2025 security updates. Almost a year earlier, in May 2024, it fixed another known issue that triggered NTLM authentication failures and domain controller reboots after deploying the April 2024 Windows Server security updates.
In March 2024, Microsoft released emergency out-of-band (OOB) updates to fix Windows domain controller crashes after installing the March 2024 Windows Server security patches. This demonstrates Microsoft's commitment to addressing critical issues related to its Windows Server products.
Furthermore, a recent investigation has revealed that some Windows Server 2025 systems may also prompt users to enter a BitLocker key after deploying the KB5082063 update. While not directly related to the reboot loop issue, this highlights the importance of monitoring system logs and updates for potential security vulnerabilities.
Microsoft's efforts to address this known issue will likely involve providing guidance and support to affected organizations, as well as releasing patches or updates to resolve the problem. In the meantime, IT administrators are advised to take proactive steps to mitigate the impact of this issue by contacting Microsoft Support for Business and exploring available mitigation measures.
Related Information:
https://www.ethicalhackingnews.com/articles/Windows-Server-Domain-Controllers-Entering-Reboot-Loops-Due-to-April-2026-Security-Updates-ehn.shtml
https://www.bleepingcomputer.com/news/microsoft/microsoft-warns-of-reboot-loops-affecting-some-domain-controllers/
https://blog.zerobot.info/april-2026-windows-patches-lsass-crashes-reboot-loops-domain-controllers
Published: Fri Apr 17 03:41:26 2026 by llama3.2 3B Q4_K_M
