How to check if someone is remotely accessing your computer

Question

I suspect that someone might be accessing my computer remotely without my knowledge. Are there any specific tools or techniques I can use to verify this and ensure my system’s security?

Answer 1

Here's a step-by-step guide to help you detect and verify if someone is remotely accessing your computer:

Initial Checks

1. Review Recent Login History:
   • Windows:
     • Press Win + R, type eventvwr, and press Enter.
     • Navigate to Windows Logs > Security, and look for Logon events (Event ID 4624). Check the Logon Type column for Remote Desktop (Type 10) or Network (Type 3) logins.
   • macOS:
     • Go to System Preferences > Sharing, and click on Remote Management (if enabled). Check the Allow access for: list.
     • Open Terminal, type last, and press Enter to view recent login history.
2. Inspect Running Processes:
   • Windows:
     • Press Ctrl + Shift + Esc to open Task Manager. In the Processes tab, look for suspicious or unfamiliar processes, especially those with "remote" or "rdp" in their name.
   • macOS:
     • Open Activity Monitor (in Applications/Utilities). Check the Process Name column for suspicious processes.

Detection Tools and Techniques

1. Network Monitoring:
   • Wireless Network:
     • Check your router's web interface for connected devices. Look for unfamiliar devices or devices with suspicious names.
   • Third-Party Tools:
     • Wireshark (free, cross-platform): Capture and analyze network traffic to detect unusual incoming connections.
     • GlassWire (free trial, Windows, macOS): A user-friendly network monitor that alerts you to suspicious activity.
2. System Configuration and Logs:
   • Check Remote Desktop Settings:
     • Windows: Ensure Remote Desktop is disabled if not in use (Settings > System > Remote Desktop).
     • macOS: Verify Screen Sharing is disabled if not in use (System Preferences > Sharing > Screen Sharing).
   • Inspect System Logs for Suspicious Activity:
     • Windows: Use the Event Viewer (as mentioned earlier) to check for unusual system events.
     • macOS: Check the System.log and Secure.log files in the Console app (in Applications/Utilities) for suspicious entries.
3. Malware Scans and Rootkit Detection:
   • Run a full scan with your antivirus software to detect malware that could be facilitating remote access.
   • Use a rootkit detection tool like Rootkit Revealer (free, Windows) or Rootkit Hunter (free, cross-platform) to identify hidden malware.

Proactive Security Measures

1. Change Passwords:
   • Update all passwords, especially for administrator accounts, using strong, unique passwords.
2. Enable Firewall and Block Incoming Connections:
   • Windows: Ensure the Windows Defender Firewall is enabled (Settings > Update & Security > Windows Security > Firewall & network protection).
   • macOS: Enable the firewall (System Preferences > Security & Privacy > Firewall).
3. Disable Unnecessary Remote Services:
   • Remote Desktop, Screen Sharing, and TeamViewer (if not in use).
4. Keep Your Operating System and Software Up-to-Date:
   • Regularly update your OS, browser, and other software to patch security vulnerabilities.
5. Use Two-Factor Authentication (2FA):
   • Enable 2FA for all accounts that support it, adding an extra layer of security.
6. Monitor Your System Regularly:
   • Schedule regular checks using the tools and techniques mentioned above.