Name:Excessive Usage Of SC Service Utility id:cb6b339e-d4c6-11eb-a026-acde48001122 version:3 date:2024-09-30 author:Teoderick Contreras, Splunk status:production type:Anomaly Description:The following analytic detects excessive usage of the `sc.exe` service utility on a host machine. It leverages Sysmon EventCode 1 logs to identify instances where `sc.exe` is executed more frequently than normal within a 15-minute window. This behavior is significant as it is commonly associated with ransomware, cryptocurrency miners, and other malware attempting to create, modify, delete, or disable services, potentially related to security applications or for privilege escalation. If confirmed malicious, this activity could allow attackers to manipulate critical services, leading to system compromise or disruption of security defenses. Data_source:
-Sysmon EventID 1
-Windows Event Log Security 4688
-CrowdStrike ProcessRollup2
search:`sysmon` EventCode = 1 process_name = "sc.exe" | bucket _time span=15m | stats values(process) as process count as numScExe by dest, _time | eventstats avg(numScExe) as avgScExe, stdev(numScExe) as stdScExe, count as numSlots by dest | eval upperThreshold=(avgScExe + stdScExe *3) | eval isOutlier=if(avgScExe > 5 and avgScExe >= upperThreshold, 1, 0) | search isOutlier=1 | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `excessive_usage_of_sc_service_utility_filter`
how_to_implement:To successfully implement this search, you need to be ingesting logs with the process name, parent process, and command-line executions from your endpoints. If you are using Sysmon, you must have at least version 6.0.4 of the Sysmon TA. Tune and filter known instances where renamed taskkill.exe may be used. known_false_positives:excessive execution of sc.exe is quite suspicious since it can modify or execute app in high privilege permission. References: -https://app.any.run/tasks/c0f98850-af65-4352-9746-fbebadee4f05/ 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: - 'Ransomware' - 'Azorult' asset_type:Endpoint confidence:50 impact:50 message:Excessive Usage Of SC Service Utility mitre_attack_id: - 'T1569' - 'T1569.002' observable: name:'dest' type:'Endpoint' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - '_time' - 'EventCode' - 'process_name' - 'process' risk_score:25 security_domain:endpoint
