Article

Transport control systems: Bespoke approaches to ICS security testing

An overview of MWR's recent security assessment of a unique transport control system

At MWR we appreciate that each Industrial Control System (ICS) is unique in both its purpose and technical construct. Because of this, each security assessment of an ICS requires a tailored plan to ensure a safe and thorough test that provides tangible results to inform our understanding of risk. The results can then be used as actions to improve the security of the system to the wider benefit of system vendors, owners, operators and those who depend on the ICS for its products or services.

MWR were recently tasked to undertake a security assessment of a transport control system. The security of this system has a direct impact on its safety. Exploitation of this system could potentially result in equipment damage, service downtime or disruption, injury and loss of life.

No system of this type had yet undergone a technical security assessment, so no previous technical testing precedent existed. MWR, working in collaboration with the client, vendors and Adelard, a safety engineering consultancy, devised a scheme of assessment appropriate for this specific transport management system.

The key first step of this task was understanding the context and architecture of the system, in order to identify key interfaces, data flows and trust relationships critical to the safe operation of the system. This included collaborating with an Adelard led hazard identification, HAZOP, workshop and working with vendor technical staff, alongside analysing standards documents, to identify potential system and protocol security weaknesses and inform an appropriate scheme of security testing.

Next, test plans, tools and techniques were developed to enable the security testing. In the case of this particular transport control system, existing vendor functional testing and debugging equipment where leveraged to provide access to radio interfaces and enable efficient testing.MWR staff also developed message generation tools specifically for the protocols used with the system. Once more, vendor engineers were involved in this process and were implicitly exposed to the security mind-set and techniques that could potentially be used against their systems.

Finally, after these preparation tasks were completed the assessment itself was conducted. MWRconsultants worked alongside engineers at the vendor’s development site to conduct the security testing, investigate issues and understand the impact of the results. The results from testing have been used to make specific technical guidance for equipment vendors; inform system owners on risks within these systems and guide standards as well as future security testing in this domain.

 

 

Accreditations

As members of CHECK we are measured against high standards set by CESG for the services we provide to Her Majesty's Government.
We are certified in the ISO 9001 quality management system (QMS) in the UK, ensuring reliable delivery of our products and services.
We are certified to comply with ISO 14001 in the UK, an internationally accepted standard that outlines how to put an effective environmental management system in place.
MWR is certified to comply with ISO 27001 to help ensure our client information is managed securely.
As an Approved Scanning Vendor MWR are approved by PCI SSC to conduct external vulnerability scanning services to PCI DSS Requirement 11.2.2.
We are members of the Council of Registered Ethical Security Testers (CREST), an organisation serving the needs of the information security sector.
MWR is a supplier to the Crown Commercial Service (CCS), which provides commercial and procurement services to the UK public sector.
MWR is a Qualified Security Assessor, meaning we have been qualified by PCI to validate other organisation's adherence to PCI DSS.