Name:Short Lived Windows Accounts id:b25f6f62-0782-43c1-b403-083231ffd97d version:6 date:2024-11-14 author:David Dorsey, Bhavin Patel, Splunk status:production type:TTP Description:The following analytic detects the rapid creation and deletion of Windows accounts within a short time frame of 1 hour. It leverages the "Change" data model in Splunk, specifically monitoring events with result IDs 4720 (account creation) and 4726 (account deletion). This behavior is significant as it may indicate an attacker attempting to create and remove accounts quickly to evade detection or gain unauthorized access. If confirmed malicious, this activity could lead to unauthorized access, privilege escalation, or further malicious actions within the environment. Immediate investigation of flagged events is crucial to mitigate potential damage. Data_source:
-Windows Event Log System 4720
-Windows Event Log System 4726
search:| tstats `security_content_summariesonly` values(All_Changes.result_id) as result_id count min(_time) as firstTime max(_time) as lastTime from datamodel=Change where All_Changes.result_id=4720 OR All_Changes.result_id=4726 by _time span=1h All_Changes.user All_Changes.dest All_Changes.Account_Management.src All_Changes.Account_Management.src_user | `security_content_ctime(lastTime)` | `security_content_ctime(firstTime)` | `drop_dm_object_name("All_Changes")` | `drop_dm_object_name("Account_Management")` | transaction user connected=false maxspan=60m | eval create_result_id=mvindex(result_id, 0) | eval delete_result_id=mvindex(result_id, 1) | search create_result_id = 4720 delete_result_id=4726 | table firstTime lastTime count user src src_user dest create_result_id delete_result_id | `short_lived_windows_accounts_filter`
how_to_implement:This search requires you to have enabled your Group Management Audit Logs in your Local Windows Security Policy and be ingesting those logs. More information on how to enable them can be found here: http://whatevernetworks.com/auditing-group-membership-changes-in-active-directory/. We also recommend adjsuting the maxspan and _time parameter to better fit your environment. known_false_positives:It is possible that an administrator created and deleted an account in a short time period. Verifying activity with an administrator is advised. References: -https://www.youtube.com/watch?v=D4Cd-KK4ctk -https://attack.mitre.org/techniques/T1078/ drilldown_searches: name:'View the detection results for - "$dest$" and "$src_user$"' search:'%original_detection_search% | search dest = "$dest$" src_user = "$src_user$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$dest$" and "$src_user$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$", "$src_user$") starthoursago=168 | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' tags: analytic_story: - 'Active Directory Lateral Movement' asset_type:Windows confidence:90 impact:70 message:A user account $user$ is created and deleted within a short time period on host $dest$ by user $src_user$ mitre_attack_id: - 'T1136.001' - 'T1136' - 'T1078.003' observable: name:'dest' type:'Hostname' - role: - 'Victim' name:'src_user' type:'User' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - '_time' - 'All_Changes.result_id' - 'All_Changes.user' - 'All_Changes.dest' risk_score:63 security_domain:access
