SCADA systems security issues

SCADA systems are used to monitor and control critical installations in oil and gas refineries, water and power distribution plants, manufacturing plants and other industrial facilities. There has been a lot of discussion about malware and security in industrial automation systems after Stuxnet. Widely viewed as the most complex piece of computer malware ever created, Stuxnet is believed to have been designed to sabotage uranium enrichment centrifuges at the Iran’s Natanz nuclear plant. If nasty malware can do that, other similar malware can do something else nasty as well.

Attacks against SCADA systems can have potentially very serious consequences. I think that we have been quite lucky that we have not seen any big disasters yet. Even though the attacks are rare at the moment, security researchers are confident that their number will increase, especially since the Stuxnet industrial sabotage worm set a successful precedent. And now there are many news on Dugu worm.

News around one month ago told that SCADA hack shut down a US water plant at 8 November 2011. This hacking attack at a US water plant has been credited to an unknown attacker (handle “pr0f” took credit) who according to hacker sources managed to access a SCADA controller and take over systems. Once again caused security experts to question the security of SCADA systems. Hacker Says Texas Town Used Three Character Password To Secure Internet Facing SCADA System. “This was barely a hack. A child who knows how the HMI that comes with Simatic works could have accomplished this,” he wrote. “You know. Insanely stupid. I dislike, immensely, how the DHS tend to downplay how absolutely (expletive) the state of national infrastructure is. I’ve also seen various people doubt the possibility an attack like this could be done,” he wrote in a note on the file sharing Web site pastebin.com. On the other hand Federal officials said there’s no evidence to support a report that hackers destroyed a pump used by an Illinois-based water utility after gaining unauthorized access to the computer system it used to operate its machinery. What is the truth in this case it is hard to say.

What is known that many industrial systems are vulnerable. Siemens Simatic is a common SCADA product and has been the subject of other warnings from security researchers according to Siemens industrial control systems are vulnerable to attack that can cause serious problems. The US Industrial Control Systems Cyber Emergency Response Team (ICS-CERT) warned earlier that Siemens’ SIMATIC S7-1200 programmable logic controllers (PLCs) are vulnerable to so-called replay attacks that can interfere with the normal operations. An attacker with access to the PLC or the automation network could intercept the PLC password and make unauthorized changes to the PLC operation. ISO-TSAP protocol is functioning to specifications; however, authentication is not performed nor are payloads encrypted or obfuscated.

White Paper On Industrial Automation Security In Fieldbus And Field Device Level is an interesting white paper (from Vacon, Nixu and F-secure) that focuses on presenting a generic overview about security in industrial automation. Security aspects of traditional fieldbuses, Ethernet-based networks and wireless communication technologies are presented. Challenges regarding data security in the field of industrial automation are discussed. The properties of industrial automation devices are described with a focus on security, tampering possibilities, and risk mitigation methods.

Many protocols used in industrial control systems were intentionally designed to be open and without security features. As long the the networks that run those protocols are kept physically separate from public network you are quite safe. For the most part SCADA systems are not necessarily designed to be connected to the internet, but engineers can put in workarounds for remote access. Anytime you do this you put in a pathway where someone can get in. And there are often case where remote devices are accessed using those non-secure protocols though unsafe networks (public telephone network, cellular network, radio waves, even Internet).

There has been long time the belief that SCADA systems have the benefit of security through the use of specialized protocols and proprietary interfaces (security through obscurity), networks are physically secured and disconnected from the Internet. Today those beliefs all do not hold anymore. There are nowadays you can find many tools on Internet to work with standard SCADA protocols (for example Wireshark can be used to decode several commonly used SCADA protocols).

The move from proprietary technologies to more standardized and open solutions together with the increased number of connections between SCADA systems and office networks and the Internet has made them more vulnerable to attacks. Modern SCADA systems should be designed so that they can be withstand the situation they are accidentally connected to Internet (it will happen sooner or later). In addition to making SCADA system itself secure, you should separate it from Internet (no connection at all or very strictly configured series of firewalls). FACT CHECK: SCADA Systems Are Online Now article tells at nearly everything is connected now. Nearly all SCADA systems are online. The addition of a simple NAT device is far from bulletproof security access control.

Most of SCADA systems in use are are old computer systems. They are usually horribly patched (“if it ain’t broken, don’t fix it”) and often run very old operating system version. Windows is very commonly used operating systems on SCADA applications, because only few SCADA-packages support other than Windows operational systems. It seems that there are many people who are not happy with the security stance being taken within their organizations around SCADA hosts. Even if you have patches up to date and current anti-malware on a host, all you have done is eliminated some of the risk (and maybe created new risks caused by fact that anti-malware software can sometimes disturb normal system operation). Add a firewall and you have reduced some of the risk. Pile on as much security as you want and people are going to find ways to disable it and make themselves vulnerable.

I wish no one had to worry about hackers in any application, but we do. Unfortunately, data security is never a non-issue.

FACT CHECK: SCADA Systems Are Online Now article mentions an interesting story on Boeing 747 (For those who do not know, modern 747′s are big flying Unix hosts with lots of Ethernet). They had added a new video system that ran over IP. They segregated this from the control systems using layer 2 – VLANs. The security researchers managed to break the VLANs and access other systems (including Engine management systems). The issue here is that all that separated the engine control systems and the open network was VLAN and NAT based filters.