A replication naming context was removed from a DC.
Removal of replication partners can affect AD health. Minimal attack relevance.
Alert: unexpected removal of replication sources from DCs.
SubjectUserNameTargetUserNameLogonTypeIpAddressWorkstationName Starting points — adapt the log source, projected fields and thresholds for your environment.
SecurityEvent
| where EventID == 4929 // An Active Directory replica source naming context was removed
| project TimeGenerated, Computer, SubjectUserName, TargetUserName, LogonType, IpAddress, WorkstationName
| sort by TimeGenerated desc
index=* sourcetype="WinEventLog:Security" EventCode=4929
| stats count earliest(_time) as first_seen latest(_time) as last_seen by ComputerName
| sort - count `# An Active Directory replica source naming context was removed — add EventData fields: SubjectUserName, TargetUserName, LogonType, IpAddress`
An Active Directory replica source naming context was removed. A replication naming context was removed from a DC.
Event 4929 is written to the Security channel by Microsoft-Windows-Security-Auditing. Advanced Audit Policy — enable the 'DS Access' subcategory (Success and/or Failure).
Alert: unexpected removal of replication sources from DCs.