Name:Sdclt UAC Bypass id:d71efbf6-da63-11eb-8c6e-acde48001122 version:8 date:2025-02-10 author:Steven Dick, Teoderick Contreras, Splunk status:production type:TTP Description:The following analytic detects suspicious modifications to the sdclt.exe registry, a technique often used to bypass User Account Control (UAC). It leverages data from Endpoint Detection and Response (EDR) agents, focusing on specific registry paths and values associated with sdclt.exe. This activity is significant because UAC bypasses can allow attackers to execute payloads with elevated privileges without user consent. If confirmed malicious, this could lead to unauthorized code execution, privilege escalation, and potential persistence within the environment, posing a severe security risk. Data_source:
-Sysmon EventID 12
-Sysmon EventID 13
search:| tstats `security_content_summariesonly` count FROM datamodel=Endpoint.Registry WHERE ((Registry.registry_path= "*\\Windows\\CurrentVersion\\App Paths\\control.exe*" OR Registry.registry_path= "*\\exefile\\shell\\runas\\command\\*") (Registry.registry_value_name = "(Default)" OR Registry.registry_value_name = "IsolatedCommand")) by Registry.action Registry.dest Registry.process_guid Registry.process_id Registry.registry_hive Registry.registry_path Registry.registry_key_name Registry.registry_value_data Registry.registry_value_name Registry.registry_value_type Registry.status Registry.user Registry.vendor_product | `drop_dm_object_name(Registry)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `sdclt_uac_bypass_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:Limited to no false positives are expected. References: -https://enigma0x3.net/2017/03/17/fileless-uac-bypass-using-sdclt-exe/ -https://github.com/hfiref0x/UACME -https://www.cyborgsecurity.com/cyborg-labs/threat-hunt-deep-dives-user-account-control-bypass-via-registry-modification/ 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: - 'Windows Defense Evasion Tactics' - 'Windows Registry Abuse' asset_type:Endpoint mitre_attack_id: - 'T1548.002' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' security_domain:endpoint
