Detects suspicious Windows service installations (MITRE ATT&CK T1543.003) by parsing System event log Event ID 7045, analyzing service binary paths, and flagging indicators of persistence mechanisms via Sysmon/EDR telemetry. Use when hunting for new-service persistence after a suspected compromise, when Event ID 7045 fires for an unfamiliar service, or during incident response to enumerate service-based persistence on Windows hosts.
Start a fresh conversation. Replace the highlighted placeholders.
Use hunting-for-unusual-service-installations to analyze [Windows System .evtx files] for Event ID 7045, identify suspicious service-installation indicators, correlate available Sysmon data, and produce a T1543.003 threat-hunting report.
Required inputs
[Windows System .evtx files]
User-approved starter prompt based on a pinned source version; check current skill requirements before running. Task evidence ↗
SKILL.md
name: hunting-for-unusual-service-installationsdescription: Detects suspicious Windows service installations (MITRE ATT&CK T1543.003) by parsing System event log Event ID 7045, analyzing service binary paths, and flagging indicators of persistence mechanisms via Sysmon/EDR telemetry. Use when hunting for new-service persistence after a suspected compromise, when Event ID 7045 fires for an unfamiliar service, or during incident response to enumerate service-based persistence on Windows hosts.domain: cybersecuritysubdomain: threat-huntingtags: - threat-hunting- T1543.003- service-installation- persistence- Event-7045- Sysmon- Windows-servicesversion: '1.0'author: mahipallicense: Apache-2.0d3fend_techniques: - Platform Hardening- System Configuration Permissions- Restore Object- Restore Database- Asset Inventorynist_csf: - DE.CM-01- DE.AE-02- DE.AE-07- ID.RA-05mitre_attack: - T1046- T1057- T1082- T1083- T1547
Hunting for Unusual Service Installations
Overview
Attackers frequently install malicious Windows services for persistence and privilege escalation (MITRE ATT&CK T1543.003 — Create or Modify System Process: Windows Service). Event ID 7045 in the System event log records every new service installation. This skill parses .evtx log files to extract service installation events, flags suspicious binary paths (temp directories, PowerShell, cmd.exe, encoded commands), and correlates with known attack patterns.
When to Use
When investigating security incidents that require hunting for unusual service installations
When building detection rules or threat hunting queries for this domain
When SOC analysts need structured procedures for this analysis type
When validating security monitoring coverage for related attack techniques
Prerequisites
Python 3.9+ with python-evtx, lxml
Windows System event log (.evtx) files
Access to live System event log (optional, for real-time monitoring)
Sysmon logs for enhanced process tracking (optional)
Steps
Parse System.evtx for Event ID 7045 (new service installed)
Extract service name, binary path, service type, and account
Flag services with suspicious binary paths (temp dirs, encoded commands)
Detect PowerShell-based service creation patterns
Identify services running as LocalSystem with unusual paths
Cross-reference with known legitimate service baselines
Generate threat hunting report with MITRE ATT&CK T1543.003 mapping
Expected Output
JSON report listing all new service installations with risk scores, suspicious indicators, and remediation recommendations
Timeline of service installation events with binary path analysis