Name:WBAdmin Delete System Backups id:cd5aed7e-5cea-11eb-ae93-0242ac130002 version:4 date:2024-11-26 author:Michael Haag, Splunk status:production type:TTP Description:The following analytic detects the execution of wbadmin.exe with flags that delete backup files, specifically targeting catalog or system state backups. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line arguments. This activity is significant because it is commonly used by ransomware to prevent recovery by deleting system backups. If confirmed malicious, this action could severely hinder recovery efforts, leading to prolonged downtime and potential data loss. Data_source:
-Sysmon EventID 1
-Windows Event Log Security 4688
-CrowdStrike ProcessRollup2
search:| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where `process_wbadmin` AND Processes.process="*delete*" AND (Processes.process="*catalog*" OR Processes.process="*backup*") by Processes.process_name Processes.process Processes.parent_process_name Processes.dest Processes.user | `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`| `wbadmin_delete_system_backups_filter`
how_to_implement:The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the `Processes` node of the `Endpoint` data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process. known_false_positives:Administrators may modify the boot configuration. References: -https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1490/T1490.md -https://thedfirreport.com/2020/10/08/ryuks-return/ -https://attack.mitre.org/techniques/T1490/ -https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/wbadmin -https://www.welivesecurity.com/2019/04/30/buhtrap-backdoor-ransomware-advertising-platform/ drilldown_searches: name:'View the detection results for - "$dest$"' search:'%original_detection_search% | search dest = "$dest$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$dest$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$") 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: - 'Ryuk Ransomware' - 'Ransomware' - 'Prestige Ransomware' - 'Chaos Ransomware' asset_type:Endpoint confidence:50 impact:30 message:System backups deletion on $dest$ mitre_attack_id: - 'T1490' observable: name:'dest' type:'Endpoint' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - '_time' - 'Processes.process_name' - 'Processes.process' - 'Processes.parent_process_name' - 'Processes.dest' - 'Processes.user' risk_score:15 security_domain:endpoint
