Managed Sentinel – Alert 121

Alert IDMS-A121
Alert NameAdd + Delete account from a privileged group within a short time frame
DescriptionIdentifies accounts that are added to privileged group and then quickly removed, which could be a sign of compromise.
Severity LevelLow
Threat IndicatorUnauthorized Access
MITRE ATT&CK TacticsPersistence
Privilege Escalation
Log sourcesWindows
False PositivesApproved changes as part of UAT/DEV testing
Recommendations1. Collect evidence of the changes in the Windows environment related to the account name created and then deleted.
2. Investigate via Azure Sentinel for any lateral movements within your network using the account name. Understand and validate what or if any other changes were done during the timeframe when the account was active into your network.
3. Identify the originator host from where the change was done
4. Perform an EDR scan on the impacted host