Translated from 日本語 • View original 
Importance of Sysmon
Sysmon (System Monitor) is a tool that collects detailed events that occur inside Windows, and traditionally had to be downloaded and deployed separately from Sysinternals. With this announcement, you can expect the following benefits as it comes standard with Windows 11 and Windows Server 2025:
- Process creation log (Event ID 1)
Detect suspicious command-line executions (e.g., 'powershell -nop -w hidden'). - Network Connection Logs (Event ID 3)
Visualize abnormal external connections such as C2 communications. - File creation log (Event ID 11)
Detect suspicious scripts generated in temporary directories. - Process access and tampering (Event ID 8, 25)
Detect unauthorized access to LSASS and process hollowing.
These detailed events provide granular information not available in traditional Windows event logs, making them essential for advanced attack detection and incident response.
Significance of Analyzing with SIEM
Sysmon logs really come into play when they are ingested into your SIEM (Security Information and Event Management).
- Correlation analysis
Combine process creation, network connectivity, and file manipulation to gain visibility into the attack lifecycle. - Improved alert accuracy
Information that tends to be noisy in a single event can be detected as "signs of attack" by correlating it on the SIEM. - Real-time detection
Leverage Sysmon's detailed logs to detect previously overlooked signs of fileless attacks and lateral expansion.
In other words**, Sysmon acts as the "fuel" of your SIEM, dramatically increasing the quality of your security operations**.
Forensic Perspectives
Sysmon logs are also extremely useful in forensic investigations after an incident.
- Identifying attack vectors
Process creation and network connection logs can reproduce how attackers infiltrated and deployed. - Evidence preservation
Detailed event logs provide reliable evidence in legal responses and internal audits. - Timeline Building
Sort Sysmon events in chronological order to clarify the overall picture of the attack.
In the past, the time and effort required for introduction and updates and the lack of support were issues, but the standard installation reduces the operational load and strengthens the foundation of forensics.
How to Activate
It seems that you can switch from "Enable or disable Windows features",
We would like to verify whether it is possible to change settings using Group Policy and Intune in the future.
Sysmon Event ID and SIEM Use Case Chart
| Sysmon Event ID | Contents | SIEM Usage Examples |
|---|---|---|
| 1 | Process Creation | Detect suspicious command-line executions and identify initial attack activity |
| 3 | Network Connectivity | Correlation Analysis to Detect C2 Communications and Abnormal External Connections |
| 6 | Driver Loading | Detect Fraudulent Drivers and Rootkits |
| 8 | Process Access | Detect access to LSASS and prevent credential theft |
| 11 | File Creation | Detect suspicious scripts and malware deployments |
| 13 | Registry Operations | Detect traces of persistence and understand attacker persistence |
| 22 | DNS Queries | Detect suspicious domain access and identify C2 communications |
| 25 | Process Hollowing | Detecting In-Memory Code Execution |
Conclusion
With Sysmon coming standard on Windows,
- Improved accuracy of attack detection
- Advanced correlation analysis in SIEM
- Streamline forensic investigations
You can expect such effects. "How to use Sysmon logs" in security operations will be a major theme in the future.
Colorkrew has a lot of experience in building and operating log aggregation and analysis, mainly using Sentinel.
Please contact us.