Start with visibility into sensitive data, then reduce unnecessary exposure in the highest-risk locations. Prioritise file shares, backups, cloud storage, and legacy repositories that hold engineering documents, credentials, and regulated data. Use least privilege, remove redundant data, and map sensitive datasets to incident response plans so teams can act safely without disrupting availability or safety.
Why This Matters for Security Teams
Data-centric cybersecurity changes the question from “Is the perimeter secure?” to “Which information would cause the most operational, safety, legal, or financial harm if exposed or altered?” In critical infrastructure, that distinction matters because engineering drawings, process recipes, credentials, safety logic, and recovery data often live in ordinary repositories that are easy to overlook. Current guidance from CISA cyber threat advisories reinforces that attackers routinely pursue the data that unlocks broader disruption, not just the loudest systems.
Teams often get this wrong by treating classification as a compliance exercise rather than a control design input. If sensitive data is not mapped to owners, locations, and dependencies, then encryption, DLP, and backups may exist without meaningfully reducing risk. For critical infrastructure, the practical objective is to reduce exposure without breaking uptime, safety engineering, or recovery processes. That means understanding where data is stored, who can reach it, and how quickly it can be isolated during an incident.
In practice, many security teams encounter the most dangerous data exposures only after an intrusion has already reached shared storage, backup systems, or legacy repositories.
How It Works in Practice
Implementation starts with a data inventory that is precise enough to support action. Security teams should identify sensitive datasets, classify them by operational impact, and map them to the systems, users, service accounts, and third parties that touch them. The useful output is not a spreadsheet for its own sake, but a control map that shows where to apply least privilege, where to segment access, and where to monitor for exfiltration or tampering.
In critical infrastructure, the highest-value targets are often file shares, engineering workstations, historian exports, backups, cloud object storage, and legacy repositories that were never designed for modern identity controls. Best practice is to reduce unnecessary copies, remove dormant access, and separate operational data from administrative data. Where feasible, encrypt sensitive datasets at rest and in transit, but do not assume encryption alone solves the problem if broad decryption rights remain in place.
- Map crown-jewel data to business processes, not just to storage platforms.
- Apply least privilege to users, service accounts, and machine identities that can read or move sensitive data.
- Protect backups and replicas with separate access paths and recovery controls.
- Log access to high-risk datasets and feed events into SIEM and incident response workflows.
- Test restoration, containment, and manual fallback procedures before an incident forces them.
For organisations facing advanced adversaries, the threat model should include theft, integrity sabotage, and operational disruption. Reports such as the Anthropic — first AI-orchestrated cyber espionage campaign report and the MITRE ATLAS adversarial AI threat matrix are useful reminders that automation can accelerate reconnaissance, targeting, and post-compromise data discovery. These controls tend to break down when critical data is scattered across unmanaged legacy systems because ownership is unclear and access patterns are hard to constrain without operational disruption.
Common Variations and Edge Cases
Tighter data controls often increase operational overhead, requiring organisations to balance protection against maintenance, recovery speed, and plant availability. That tradeoff is especially visible in environments that depend on shared engineering files, third-party support access, or archived operational records that must remain reachable during outages.
There is no universal standard for this yet, but current guidance suggests prioritising data segmentation and access reduction before attempting full data transformation projects. In safety-critical environments, security teams may need compensating controls rather than immediate relocation of every dataset. For example, a legacy repository may remain in place if access is tightly bounded, monitoring is strong, and the data set is minimised. Likewise, backup hardening may matter more than endpoint tooling if recovery stores contain credentials or configuration states that could enable rapid re-compromise.
Where AI tools are used to search, summarise, or classify sensitive operational content, governance must extend to prompts, connectors, and output handling. The same caution applies if AI agents can reach data repositories or execute actions on their behalf. In those cases, data-centric security should be paired with identity controls for non-human identities and agent permissions, not treated as a standalone storage problem. Regulatory pressure can also shape priorities, and the EU NIS2 Directive is a useful reference point for resilience and governance expectations in essential services.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
MITRE ATLAS address the attack surface, NIST CSF 2.0 set the technical controls, and NIS2 define the regulatory obligations.
| Framework | Control / Reference | Relevance |
|---|---|---|
| NIST CSF 2.0 | PR.DS-1 | Sensitive data should be identified and protected across critical repositories. |
| MITRE ATLAS | AML.TA0003 | Adversaries may use AI to accelerate discovery of sensitive data paths. |
| NIS2 | Essential services need governance and resilience for critical data handling. |
Classify crown-jewel data, then apply protection controls where the data actually lives.
Related resources from NHI Mgmt Group
- How should security teams implement identity centric ZTNA in hybrid environments?
- How should security teams implement microsegmentation for sensitive data environments?
- How should security teams implement data discovery in complex environments?
- How should security teams implement data encryption alongside data loss prevention in cloud and SaaS environments?