SYSMON - CMD

Overview

The SYSMON command in Windows is a utility that monitors and logs system activity to the Windows event log. It is primarily used for system security and forensic analysis. It helps track process creations, network connections, and changes to file creation time by logging this information for further analysis. It can be most effectively used in environments where maintaining security and understanding all system interactions is crucial, such as servers or critical workstations.

Syntax

The basic syntax for using SYSMON is as follows:

sysmon [options]

Common Usage

sysmon -i [config.xml]        # Install Sysmon with the specified configuration.
sysmon -c [config.xml]        # Modify the current Sysmon configuration.
sysmon -u                     # Uninstall Sysmon.

Options/Flags

  • -i [config.xml]: Install Sysmon with a configuration file specified as config.xml. If no configuration is specified, Sysmon will start with default settings.
  • -c [config.xml]: Update and reload the configuration based on the supplied configuration file.
  • -u: Uninstall Sysmon from the system, removing all traces and stopping logging.
  • -h: Display help for command usage.

Examples

Example 1: Installing Sysmon with a Configuration File

sysmon -i C:\config\sysmonconfig.xml

This command installs Sysmon with the settings specified in sysmonconfig.xml.

Example 2: Updating Sysmon Configuration

sysmon -c C:\config\updated_sysmonconfig.xml

Updates the currently installed Sysmon configuration using the updated_sysmonconfig.xml file.

Example 3: Uninstalling Sysmon

sysmon -u

Stops Sysmon monitoring and removes the application from the system.

Common Issues

  • Permission Errors: Ensure Sysmon is run with administrator privileges, otherwise, it may fail to install or capture logs effectively.
  • Configuration Errors: Errors in the configuration file can prevent Sysmon from monitoring specified events. Validate the XML file for errors before using it.

Integration

Sysmon can be integrated with other tools like PowerShell scripts to automate and trigger actions based on log data. Here is an example of a simple batch file that checks Sysmon logs and triggers an action:

@echo off
wevtutil qe Microsoft-Windows-Sysmon/Operational /q:"*[System[EventID=1]]" /f:text | find "cmd.exe"
if %errorlevel% == 0 (
    echo Potential unauthorized command execution detected.
)

This batch script checks for event logs where cmd.exe was executed, signaling potential unauthorized command execution.

  • Event Viewer (eventvwr): Used to view the logs that Sysmon generates.
  • Windows Security Auditing: Tools and commands under Windows Security that allow monitoring and reacting to security events.

For further reading and more detailed information, you can visit the Sysinternals Sysmon page which provides comprehensive details and updates to the tool.