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Microsoft Windows domain controller restart-loop disruption

Service Disruption
First reported
Last updated
Happening score
H score 25
1 unique sources, 1 articles

Summary

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Microsoft confirmed a service disruption affecting Windows domain controllers after the April 2026 security update KB5082063. The issue can trigger LSASS crashes and repeated restarts, which can stop authentication and directory services and leave a domain unavailable. The impact is limited to environments using Privileged Access Management (PAM), but the outage risk is operationally serious for affected organizations.

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Timeline

  1. 17.04.2026 10:59 2 articles · 1mo ago

    Microsoft discloses domain controller restart loops after KB5082063

    Initial Disclosure

    Microsoft disclosed that some Windows domain controllers can enter restart loops after the April 2026 security update KB5082063 triggers LSASS crashes during startup in non-Global Catalog domain controllers that use Privileged Access Management. The affected systems may repeatedly reboot, stopping authentication and directory services from functioning and potentially rendering the domain unavailable, while Microsoft said it is working on a fix and advised administrators to contact Microsoft Support for Business for mitigation.

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