System security access was removed from an account
An account had a User Right Assignment (`Logon right` or `Privilege`) revoked.
Event ID 4718 logs when a user right (`Access Right`) is removed from an account (`LsaRemoveAccountRights`). Commonly seen during administrative cleanup, hardening enforcement, or adversarial denial-of-service against monitoring accounts.
Failure Reason / Root Cause:
User right assignment revoked from `TargetSid`.
Raw Event XML snippet
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
<System>
<Provider Name="Microsoft-Windows-Security-Auditing" Guid="{54849625-5478-4994-A5BA-3E3B0328C30D}" />
<EventID>4718</EventID>
<Version>0</Version>
<Level>0</Level>
<Task>12544</Task>
<Opcode>0</Opcode>
<Keywords>0x8020000000000000</Keywords>
<TimeCreated SystemTime="2026-07-17T09:54:44.887Z" />
<EventRecordID>1048576</EventRecordID>
<Correlation />
<Execution ProcessID="612" ThreadID="1024" />
<Channel>Security</Channel>
<Computer>DC01.enterprise.internal</Computer>
<Security />
</System>
<EventData>
<Data Name="SubjectUserSid">S-1-5-18</Data>
<Data Name="SubjectUserName">SYSTEM</Data>
<Data Name="SubjectDomainName">NT AUTHORITY</Data>
<Data Name="SubjectLogonId">0x3e7</Data>
<!-- Event telemetry fields specific to System security access was removed from an account -->
</EventData>
</Event>Recommended actions
- Verify if service accounts lost required logon rights (`SeServiceLogonRight`) causing production outages.