Sysmon, short for System Monitor, is a Windows system service and device driver that logs system activity to the Windows event log. It provides detailed information about process creations, network connections, and file creation time changes, among other activities. Sysmon is part of the Sysinternals suite, which is a collection of utilities developed by Microsoft for advanced system and security management.

Sysmon is particularly useful for security monitoring and incident response. It allows administrators to track malicious activities by providing detailed logs that can be analyzed to detect anomalies or unauthorized access.

Examples:

1. Installing Sysmon:

   To use Sysmon, you first need to download it from the Sysinternals website. Once downloaded, you can install it using the command prompt or PowerShell.

   • Open Command Prompt as an Administrator.
   • Navigate to the directory where Sysmon is located.

   • Execute the following command to install Sysmon with a basic configuration:

     sysmon -accepteula -i sysmonconfig.xml

   The -accepteula flag is used to automatically accept the End User License Agreement. The -i flag specifies the configuration file. The sysmonconfig.xml file should define the events you want to monitor.

2. Creating a Sysmon Configuration File:

   A Sysmon configuration file is an XML file that specifies which events Sysmon should log. Here's a simple example of a configuration file:

   <Sysmon schemaversion="4.22">
    <EventFiltering>
      <ProcessCreate onmatch="include">
        <Image condition="end with">.exe</Image>
      </ProcessCreate>
    </EventFiltering>
   </Sysmon>

   This configuration logs all process creation events for executable files.

3. Updating Sysmon Configuration:

   If you need to update the Sysmon configuration, you can do so without uninstalling it. Use the following command:

   sysmon -c sysmonconfig.xml

   This command updates Sysmon with the new configuration specified in sysmonconfig.xml.

4. Uninstalling Sysmon:

   If you need to remove Sysmon from your system, use the following command:

   sysmon -u

   This command uninstalls Sysmon and removes all associated logs.

5. Viewing Sysmon Logs:

   Sysmon logs events to the Windows Event Viewer under the "Applications and Services Logs" -> "Microsoft" -> "Windows" -> "Sysmon" -> "Operational" path. You can view these logs using the Event Viewer application or by using PowerShell:

   Get-WinEvent -LogName "Microsoft-Windows-Sysmon/Operational" | Select-Object -First 10

   This PowerShell command retrieves the first 10 Sysmon events from the log.