SCADA attacks are on the rise, according to the 2015 Dell Security Annual Threat Report released this week. The report found that in 2014 the number of attacks on Supervisory Control and Data Acquisition (SCADA) systems doubled compared to the previous year. Most of these attacks occurred in Finland, the United Kingdom, and the United States, probably due to the fact that in these countries SCADA systems are more likely to be connected to the Internet.

‘Since companies are only required to report data breaches that involve personal or payment information, SCADA attacks often go unreported,’ said Patrick Sweeney, executive director, Dell Security. ‘This lack of information sharing combined with an aging industrial machinery infrastructure presents huge security challenges that will to continue to grow in the coming months and years.’

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Since SCADA systems control key functions in critical infrastructure, such as utilities, oil and gas pipelines, airports and nuclear plants, successful attacks on SCADA systems could potentially cause disruptions in services that we all depend on every day. For this reason, SCADA attacks are often politically motivated and backed by foreign state actors with motives such as industrial espionage or military sabotage.

Many SCADA and ICS (Industrial Control Systems) systems were built decades ago when cyber security was not yet an issue. To add cyber security defenses to these systems is a major task, coupled with the fact that due to their critical nature, downtime for system upgrades is virtually impossible.

How to improve SCADA security

Given these challenges, what can be done to improve the security of critical infrastructure? Here are five ways to improve SCADA security:

Air-gap systems

Since many SCADA systems do not include cyber security controls, it is important to physically separate these systems from the Internet and corporate network. If the systems are connected to the network, strong firewalls, intrusion detection systems and other security measures must be put in place to protect against unauthorized intrusion.

Avoid default configurations

Avoid using default configurations on network and security appliances. Factory passwords must be changed immediately and a system of strong passwords and regular password updating should be enforced.

Apply USB & portable device security

Since air-gapped systems are not connected to the network, often the only way to bring files in and out of the SCADA system is by using portable media such as USB drives or DVDs. As key attack vectors for air-gapped networks, it is very important to deploy a portable media security system that thoroughly scans portable devices for any threats before they are allowed to connect to the secure SCADA network.

Defend against advanced persistent threats (APT)

Attacks are becoming more and more sophisticated, with malware lying in wait undetected for a long period of time. It is important to fight APT’s at different levels; not only trying to prevent APT’s entering the network, but also detecting APT’s that have already gained entry. An effective way to detect APT’s is to use a multi anti-malware scanner that will scan files with multiple anti-virus engines using a combination of signatures and heuristics and will therefore be able to detect more threats.

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In addition, technologies such as data sanitisation can prevent zero-day and targeted attacks that may be missed by anti-malware engines by converting files to different formats and removing any possible embedded threats and scripts. Devices should be continually monitored for any abnormal activity and files on the network should be continually scanned with multiple anti-virus engines; a threat that was previously not detected could be found by an updated signature database.

Perform penetration testing

Regular penetration testing and vulnerability assessments, if possible conducted by a third party, are very helpful to get realistic input on the current security level and shed light on which areas still need additional security precautions.

The above measures, along with employee awareness training and continuous evaluation, will significantly boost the security of critical infrastructure systems.

Sourced from Deborah Galea, manager, OPSWAT