Observations about the Siemens PLC vulnerability

Thursday July 15 a disclosure was made about the Siemens SIMATIC PLC WINCC cyber vulnerability. Arguably, it is the first malware in the wild targeted specifically at industrial control systems. The following issues concern me:
- Siemens SIMATIC PLCs are used throughout the industrial (more than just critical) and DOD infrastructures globally.
- According to Stephan Brier, every SIMATIC user has the privileges of the fixed sysadmin server role by default and the MSSQLServer is installed with SYSTEM privileges - so much for security by design.
- The drivers were digitally signed using the digital signature of a large and well-known semiconductor manufacturer. 
- The vulnerability spreads via USB drives and runs automatically when a shortcut icon is displayed on a user's screen.
- Within about 15 minutes of the notice being posted on Ron Southworth’s SCADA listserve and Bob Radvanovsky’s SCADA listserve, each was hit with a DOS. Coincidence?
- As of Sunday July 18, there has been no emergency phone call from NERC CIPC on this vulnerability. Why?

As best as I can tell, this is not an attack, but a vulnerability disclosure. US CERT is treating this as a Microsoft problem (not a control system problem and is not shown on the US CERT Control Systems website) and Microsoft is treating this as a user privileges problem. With the lack of adequate control system cyber forensics, it can be close to impossible to find this vulnerability. This should certainly be a call to arms, but is it?
Joe Weiss

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  • <p>While it is true that Siemens PLCs do not run WinCC as their operating system, WinCC is the HMI that is used when you buy both a PLC and an HMI panel from Siemens. The available information is becoming much more complete, and the picture does't look good. Perhaps you would like to know that the original news post came from IDG after a call with Siemens communication leader, Michael Krampe. So, we're getting the data direct from Siemens.</p>


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