How do organisations implement Cyber-Informed Engineering (CIE)?

How CIE changes the engineering workflow

Cyber-Informed Engineering shifts security left into the engineering process itself. Instead of treating cyber controls as a later overlay, teams define the functions that must keep working, identify the attack paths most likely to matter, and engineer the system so those paths are harder to exploit. In practice, this means security decisions are made alongside safety, reliability, and performance decisions.

That change matters because CIE is not only about adding more controls. It is about choosing the right controls for the system’s real operating context, including the dependencies that create unacceptable exposure if they fail. For OT-heavy environments, the OT Security Guide is a useful companion because it covers segmentation, the Purdue model, and industrial control boundaries that often shape CIE implementation.

CIE works best when the engineering team can explain why a function is essential, what would break if it were manipulated, and which trust relationships are actually necessary. That is what turns security from a checklist into an architecture decision.

What organisations actually do when they implement CIE

Implementation usually starts with a consequence-driven view of the system. Teams identify the essential process functions, map how an attacker could interfere with them, and then redesign the environment so that compromise is harder to reach and easier to contain. The goal is not perfect prevention, but materially better resistance, detection, and recovery.

Common engineering moves include segmentation, reducing exposed pathways, hardening high-value components, limiting unnecessary connectivity, and removing assumptions that one compromised system should be trusted by another. In industrial settings, CISA’s Industrial Control Systems resources are relevant because they reflect the operational realities of these environments, where availability and safety often constrain how far security can be pushed.

Design review is not a one-time activity. CIE has to be revisited when process logic, remote access, asset placement, or recovery design changes, because a new connection or dependency can invalidate the original assumptions. That is why CIE is as much a governance habit as a technical design approach.

Where CIE usually succeeds or fails in practice

CIE succeeds when organisations are willing to engineer around mission-critical functions rather than around organisational silos. It fails when the effort is reduced to generic hardening, because the most important question is not “what controls exist” but “what attack path would actually threaten the essential function.” The design target is resilience under realistic compromise, not just compliance with a baseline.

Another common failure mode is overconfidence in perimeter controls or static segmentation. If remote maintenance, vendor pathways, or shared administrative access remain broad, the system can still be reachable through a path that bypasses the intended protections. For that reason, the CISA Secure by Design guidance aligns well with CIE thinking because both push teams to remove insecure defaults and reduce avoidable trust.

Organisations also underestimate recovery design. If an engineered safeguard prevents one failure mode but leaves restoration slow, manual, or poorly tested, the result may be a more fragile system rather than a safer one.

Risk and Threat Considerations

CIE is valuable precisely because industrial and engineered systems are attractive targets for disruption, manipulation, and downtime. The main risk is not just compromise, but compromise that changes process behaviour, impairs visibility, or forces unsafe manual operations. Once trust relationships are too broad, a single foothold can become a route to process impact.

Failure mechanism: Attackers exploit weak segmentation, over-trusted remote access, or poor recovery assumptions to move from IT-adjacent access into systems that control or influence essential functions. If engineering decisions do not account for realistic attack paths, the system may remain reachable even after visible controls are added.

Impact: The result can be loss of availability, degraded safety margins, corrupted process state, or extended recovery time. In critical environments, that means CIE is not just about cyber hygiene, it is about preventing cyber events from becoming operational incidents.

Practitioner Guidance

What to prioritise: Start with the functions whose loss or manipulation would matter most, then design around those functions before adding broader security controls. If a control does not reduce an actual attack path to an essential function, it is probably not the first control to fund.

What to verify: Validate that segmentation, access paths, and resilience assumptions still match the current architecture, not the original design. If the process, network, or vendor access model has changed, re-run the CIE review rather than assuming the prior analysis still holds.

Common mistake: Treating CIE as a documentation exercise instead of an engineering discipline. The practical test is whether the system is harder to manipulate, easier to contain, and faster to recover after a realistic compromise.

Practitioner takeaway: The strongest CIE programmes focus on essential functions and attack paths first, then prove that the design still holds when real operational change introduces new trust or connectivity.

Related resources from NHI Mgmt Group

• How does Cyber-Informed Engineering (CIE) work?
• Cyber-Informed Engineering (CIE)
• When should organisations prioritise Zero Standing Privilege for non-human identities?
• How can organisations reduce secret leakage in ServiceNow at scale?