Name:Windows Findstr GPP Discovery id:1631ac2d-f2a9-42fa-8a59-d6e210d472f5 version:3 date:2024-09-30 author:Mauricio Velazco, Splunk status:production type:TTP Description:The following analytic detects the use of the findstr command to search for unsecured credentials in Group Policy Preferences (GPP). It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions involving findstr.exe with references to SYSVOL and cpassword. This activity is significant because it indicates an attempt to locate and potentially decrypt embedded credentials in GPP, which could lead to unauthorized access. If confirmed malicious, this could allow an attacker to escalate privileges or gain access to sensitive systems and data within the domain. 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 (Processes.process_name=findstr.exe AND Processes.process=*sysvol* AND Processes.process=*cpassword*) by Processes.dest Processes.user Processes.parent_process_name Processes.process_name Processes.process Processes.process_id Processes.parent_process_id Processes.original_file_name | `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `windows_findstr_gpp_discovery_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 leverage findstr to find passwords in GPO to validate exposure. Filter as needed. References: -https://attack.mitre.org/techniques/T1552/006/ -https://pentestlab.blog/2017/03/20/group-policy-preferences/ -https://adsecurity.org/?p=2288 -https://www.hackingarticles.in/credential-dumping-group-policy-preferences-gpp/ -https://support.microsoft.com/en-us/topic/ms14-025-vulnerability-in-group-policy-preferences-could-allow-elevation-of-privilege-may-13-2014-60734e15-af79-26ca-ea53-8cd617073c30 drilldown_searches: name:'View the detection results for - "$dest$" and "$user$"' search:'%original_detection_search% | search dest = "$dest$" user = "$user$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$dest$" and "$user$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$", "$user$") 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 Privilege Escalation' asset_type:Endpoint confidence:80 impact:70 message:Findstr was executed to discover GPP credentials on $dest$ mitre_attack_id: - 'T1552' - 'T1552.006' observable: name:'dest' type:'Hostname' - role: - 'Victim' name:'user' type:'User' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - '_time' - 'Processes.user' - 'Processes.dest' - 'Processes.process_name' - 'Processes.process' - 'Processes.dest' - 'Processes.user' - 'Processes.parent_process_name' - 'Processes.process_name' - 'Processes.process_id' - 'Processes.parent_process_id' - 'Processes.original_file_name' risk_score:56 security_domain:endpoint
