How to Use Autoruns

How to Use Autoruns to Detect and Remove Malware on Windows

In today’s cybersecurity landscape, malware often embeds itself into system processes to ensure persistence at startup. Detecting and removing such threats is crucial for maintaining system integrity. Sysinternals Autoruns, a powerful tool from Microsoft, helps users identify and manage programs that automatically launch when Windows starts. This guide by Atrity Info Solutions will walk you through using Autoruns to detect and remove potential malware threats from your Windows machine.

Note: This guide is designed for personal and small business use. For enterprise security concerns, organizations should follow their incident response protocols.

What is Autoruns?

Autoruns is a free Microsoft tool that displays all programs configured to start automatically when Windows boots or a user logs in. While many legitimate applications—such as email clients—utilize startup entries for convenience, malware often exploits these mechanisms for persistence.

Key Features of Autoruns

Autoruns categorizes startup programs across multiple tabs, helping users analyze various auto-start locations. Here’s an overview:

  • Logon: Displays programs configured to run at user login, including registry run keys—often exploited by malware.
  • Explorer: Lists shell extensions, browser helper objects, toolbars, and other auto-start mechanisms tied to Windows Explorer.
  • Internet Explorer: Shows add-ons, toolbars, and helper objects linked to Internet Explorer.
  • Scheduled Tasks: Identifies tasks set to launch at startup or login, frequently misused by malicious software.
  • Services: Lists Windows services configured to run automatically at startup.
  • Drivers: Displays device drivers, which malware may exploit for deeper system access.
  • Image Hijacks: Highlights registry modifications that redirect legitimate processes to execute malicious files.
  • AppInit DLLs: Shows DLLs loaded into processes at startup.
  • Boot Execute: Displays processes set to run during early system startup, a target for advanced malware.
  • Known DLLs: Lists system DLLs—any unexpected modifications could indicate infection.
  • Winlogon: Displays processes triggered during user login, a common target for persistent threats.
  • Winsock Providers: Lists network-related components, which can be altered to intercept or manipulate network traffic.
  • Print Monitors: Shows printer-related DLLs, which malware can exploit.
  • LSA Providers: Lists authentication-related processes, which can be hijacked for credential theft.

How to Identify Suspicious Software Using Autoruns

Understanding the Autoruns interface is just the first step. Here’s how to spot potential malware:

Steps to Identify Malware:

  1. Check for Unknown Entries: Research unfamiliar applications online.
  2. Verify Publisher and Description: Entries lacking a valid publisher or description warrant investigation.
  3. Analyze File Location: Malware often hides in unusual directories, such as temporary folders.
  4. Scan with VirusTotal: Right-click a suspicious entry and select “Check VirusTotal” to scan the file against multiple antivirus engines.
  5. Review Scheduled Tasks: Unexpected scheduled tasks may indicate malware persistence.

Example of Malware Detection:

  • You discover an entry labeled “System Monitor Service” with no publisher information.
  • The file path leads to an obscure location, such as C:\Users\Public\AppData\random.exe.
  • Online searches yield no relevant information.
  • Running a VirusTotal scan confirms it as malware.

How to Remove Malware with Autoruns

Once you’ve identified a suspicious entry, follow these steps to remove it:

  1. Terminate the Process: Use Task Manager or a tool like Process Explorer to stop the malware process.
  2. Locate the File: Right-click the suspicious entry in Autoruns and choose “Open File Location.”
  3. Verify the File Hash: Use tools like PeStudio to generate a file hash and compare it against VirusTotal.
  4. Delete Startup Entries: In Autoruns, right-click the entry and select “Delete.”
  5. Remove the Malware File: Navigate to the file’s location in Windows Explorer and delete it.
  6. Restart Your PC: Ensure that no traces of the malware remain after reboot.

Best Practices for Using Autoruns

Autoruns is a powerful tool, but it should not be your sole defense against malware. Follow these best practices for enhanced security:

  • Backup Your Data: Regularly back up important files in case malware removal requires a system restore.
  • Use Reliable Antivirus Software: If your current antivirus failed to detect the malware, consider upgrading to a more robust solution.
  • Utilize the Autoruns Compare Feature: Save an “Autoruns Data” (.arn) file from a clean system state to compare future scans.
  • Perform Regular Scans: Running Autoruns periodically helps identify new threats before they cause significant damage.

Conclusion

Autoruns is an invaluable tool for detecting and removing persistent malware on Windows systems. By following this guide from Atrity Info Solutions, you can effectively identify suspicious programs, confirm their legitimacy, and eliminate potential threats.

For businesses and enterprises, consider investing in advanced security solutions that offer real-time threat detection and incident response capabilities to strengthen overall cybersecurity resilience.