Name:Windows Multiple Accounts Deleted id:49c0d4d6-c55d-4d3a-b3d5-7709fafed70d version:6 date:2024-11-13 author:Mauricio Velazco, Splunk status:production type:TTP Description:The following analytic detects the deletion of more than five unique Windows accounts within a 10-minute period, using Event Code 4726 from the Windows Security Event Log. It leverages the `wineventlog_security` dataset, segmenting data into 10-minute intervals to identify suspicious account deletions. This activity is significant as it may indicate an attacker attempting to erase traces of their actions. If confirmed malicious, this could lead to unauthorized access removal, hindering incident response and forensic investigations. Data_source:
-Windows Event Log Security 4726
search:`wineventlog_security` EventCode=4726 status=success | bucket span=10m _time | stats count dc(user) as unique_users values(user) as user values(dest) as dest by EventCode signature _time src_user SubjectDomainName TargetDomainName Logon_ID | where unique_users > 5 | `windows_multiple_accounts_deleted_filter`
how_to_implement:To successfully implement this search, you need to be ingesting Domain Controller events with the Windows TA. The Advanced Security Audit policy setting `Audit User Account Management` within `Account Management` needs to be enabled. known_false_positives:Service accounts may be responsible for the creation, deletion or modification of accounts for legitimate purposes. Filter as needed. References: -https://attack.mitre.org/techniques/T1098/ drilldown_searches: name:'View the detection results for - "$src_user$"' search:'%original_detection_search% | search src_user = "$src_user$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$src_user$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$src_user$") 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: - 'Azure Active Directory Persistence' asset_type:Endpoint mitre_attack_id: - 'T1098' - 'T1078' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' security_domain:endpoint
