TrendLabs^SM has created a STUXNET Scanner Tool to further help administrators identify clues to determine which computers in their networks are still infected by STUXNET.

A few months ago, STUXNET targeted SCADA systems—critical control systems that run complex infrastructure such as those that run transportation systems, water systems, and oil refineries, among others. STUXNET searches SCADA-related strings in order to view project databases and information stored in critical systems.

Given the nature of the attack, administrators naturally want to be doubly sure that none of their systems are infected by this malware. Despite providing immediate protection for infected systems, we are still receiving reports from customers who need help to ensure that all of their systems are free of this particular threat.

This STUXNET Scanner Tool may be downloaded for free here.

This tool helps administrators identify infected machines within their own networks even if STUXNET is not sending out or receiving communications. As we have explained in previous blog entries and in the information page STUXNET Malware Targets SCADA Systems, STUXNET installs both a server and a client component to enable the Remote Procedure Call (RPC) routine in an infected computer so it can communicate with other infected systems for the purpose of updating itself and the systems it communicates with.

How the STUXNET Scanner Tool Works

Once installed and run, the tool enumerates live IP addresses within the internal network and sends spoofed packets similar to the packets sent by known STUXNET variants. Any host infected by STUXNET will respond to this spoofed packet. Through this, network administrators can easily identify which IPs are infected within the network, thereby helping them perform the necessary actions to isolate and clean the said systems.

Trend Micro has been protecting users from all known STUXNET-related malware through the Trend Micro™ Smart Protection Network™.

STUXNET has also been discussed in the following Malware Blog entries:

• Cybercriminals Hone in on Critical Systems
• Stuxnet Used in Blackhat SEO Campaign
• Exploits for Windows Shortcut Vulnerability in the Wild

Special thanks to threat solution engineer Yuki Chen and threat analyst Joseph Cepe for contributing to the creation and testing of this tool.

Update as of November 16, 2010 9:37 p.m. UTC

When using this tool, users are advised to follow the standard operating procedure of their respective organizations for conducting penetration testing. It is likewise important to note that the STUXNET Scanner Tool acts as the client in the STUXNET peer-to-peer (P2P) communication routine. It attempts to communicate with the RPC server component from the given list of IP addresses. IDS events may also be triggered by this tool whenever it simulates STUXNET network communication.

The STUXNET Scanner Tool uses a fixed universally unique identifier (UUID), which allows it to have very minimal cases of false positives. Just the same, users are advised to scan the machine for infection. Users can utilize free tools like Trend Micro’s HouseCall to scan their systems.