Cyber Resilience in a Borderless Enterprise – Considerations for Critical Infrastructure
The ICT landscape has markedly changed over the past five years; and change will not stop in the next five. Cloud adoption accelerates at pace and most organisations now use at least one of the popular as-a-service solutions from Google, Amazon and Microsoft. Even in the critical infrastructure industry, where operational technology networks were traditionally segregated from the rest of the corporate network, we are seeing a transition to cloud technology in refresh projects; particularly in the areas of monitoring, data analysis and proactive support systems.
Flexible cloud-based infrastructure and its commodity pricing will progressively see ISC SCADA systems succumb to the allure of these platforms but what’s really driving critical infrastructure providers to adopt the cloud and seek ways they can use modern cyber security controls to remain secure?
As-A-Service Value Propositions
The primary value proposition driving any transition is the reduction of cost, in this case specifically technology costs, coupled with increased agility. Critical infrastructure companies are late to the party, with operational technology systems always having been considered different to their corporate IT cousins, in terms of security needs. Critical infrastructure organisations are finding themselves with an ROI that favours cloud services adoption, with its open standards, common signalling protocols, web application interfaces and 4G accessible mobile applications. Business functions will certainly make the first move, and as security and data integrity considerations are addressed the more vulnerable OT functions will follow.
Stability is also a consideration, as cloud service providers have built massive redundancy in their solution architecture and their supporting infrastructure and services. Increasingly as cloud providers seek to further differentiate their offerings through value-added services like platform integrity and security management, SCADA businesses will shift to the cloud to exploit its inherent benefits and build OT resilience, while at the same save themselves money.
Cloud Security for Critical Infrastructure Systems
Traditionally, legacy technology platforms carried residual levels of unmanaged cyber security risk. As a result, attacks on individual components, which could have a catastrophic impact, were frequently mitigated by the complete isolation of the system. Attackers would invariably need direct physical access to the SCADA device’s interface to launch an attack, and this lowered the overall risk significantly.
A shift to a cloud-based solution means the security once provided by the previous isolation of the system is no longer assured. Now, rather than one local system at risk, a compromised cloud platform could afford the attacker complete control over the entire operational network. As critical infrastructure companies begin to aggregate their ICT and OT systems to improve their digital operating models and customers’ experience the importance of effective public cloud based cyber security becomes an imperative.
This is because at the same time as the risk surface is increasing in size, hackers are leveraging the opportunity to attack the platform, in an effort to compromise their interfaces and potentially gain a foothold in their network as part of a longer-term initiative.
Critical Infrastructure Security Controls
Even the simplest of denial of service attacks on a cloud platform could render a SCADA or ICS system unmanageable. Furthermore, strong identification and authentication should be inherent, since it’s important to guarantee the administrator logging into the web interface is who they say they are. Backup and recovery solutions and associated failover procedures should also be built into the organisation’s work instructions, and if the technology vendor has an option for redundancy built into the cloud platform, it should be deployed.
As this platform shift begins to occur organisations will increasingly deploy behavioural anomaly detection (BAD) technologies to monitor application and cloud access and report any suspicious activities. By detecting suspicious or anomalous behaviour, these BAD technologies are ideal for detecting control systems attacks for two reasons: (i) BAD technologies are very good at detecting unusual activity in a highly repetitive OT environment; and (ii) advancement of machine learning and artificial intelligence can quickly correlate and make sense of the millions of security event logs these systems produce.
Security monitoring has always been used by critical infrastructure providers to detect systems failures and configuration changes. The new paradigm of as-a-service computing doesn’t change anything when it comes to the requirements for security event monitoring. What it changes is context. New log sources, such as OT, ICT applications and cloud services, must all be monitored against normal behavioural baselines. Critical infrastructure organisations will need their SOC teams to more completely integrate the activities of their networks and corporate security teams.
The best outcomes are assured by converging OT, ICT and cloud service security management and monitoring, so that one team can effectively handle threat management for their business as they seek to optimise the security of hybrid cloud environments.