Software made by Siemens and targeted by the Stuxnet malware is still full of other dangerous vulnerabilities, according to Russian researchers whose presentation at the Defcon security conference earlier this year was cancelled following a request from the company.
Sergey Gordeychik, CTO of Moscow-based Positive Technologies, was scheduled to give a presentation in July at Defcon, but it was abruptly pulled after Siemens asked for more time to patch its WinCC software.
WinCC is a type of SCADA (Supervisory Control And Data Acquisition) system, which is used to manage a variety of industrial processes in factories and energy utilities. The type of software underpins much of what's deemed critical infrastructure by countries and has in recent years received closer examination by computer security experts.
Iran used WinCC to control centrifuges for refining uranium. Weaknesses in the software - combined with vulnerabilities in Microsoft's Windows OS - allowed the malicious software called Stuxnet to disrupt the centrifuges, an act of sabotage linked to the US and Israel.
Gordeychik agreed to suspend his presentation at Defcon, but on Thursday presented an overview of his WinCC research at the Power of Community security conference in Seoul with Gleb Gritsai, a colleague on the company's penetration testing team. They withheld the specific details of the vulnerabilities since Siemens has not released patches.
The team has found more than 50 vulnerabilities in WinCC's latest version, so many that Siemens has worked out a roadmap to patch them all, Gordeychik said in an interview. Most are problems that would allow an attacker to take over a WinCC system remotely.
Still, "it's easy to find a vulnerability in WinCC," Gordeychik said. "You can just point at it."
Gritsai showed how, when an industrial system operator is using the same browser to access both the open Internet and WinCC's web interface, a vulnerability can be exploited to obtain login credentials for the back-end SCADA network.
Several cross-site scripting flaws have been found in WebNavigator, Siemens' web-based human-machine interface that allows a WinCC-controlled operation to run with Internet Explorer.
It's not unusual for organisations that have WinCC's web interface installed on the desktop to also use the browser on the Internet, Gritsai said. For example, an employee may be chatting on Facebook at the same time they're managing a nuclear plant, he said.
Siemens has been very receptive to Positive Technologies' findings, Gordeychik said. With Stuxnet, Siemens appears to be experiencing the same sort of security wake-up call that Microsoft had when pernicious malware such as the Code Red worm appeared in 2001.
"I'm really surprised," Gordeychik said. "Other SCADA vendors don't want to talk about security at all."
Positive Technologies also released two security tools on Thursday relating to WinCC. The first is a module called WinCC Harvest for the Metasploit penetration testing tool that allows an attacker to collect information from a SQL database within a Siemens SIMATIC WinCC SCADA system.
The other tool, called PLCScan, is used to scan for programmable logic controllers, which are the electronic devices used to control machines in SCADA systems.