Industrial controller (PLC) CRA Risk Assessment Starter
A pre-filled Cyber Resilience Act risk assessment for a programmable logic controller or edge automation controller driving plant equipment, engineered and maintained by an integrator. It covers the Annex III/IV classification and the conformity route that follows from it, a starter asset inventory, a STRIDE threat analysis mapped to Annex I Part I essential cybersecurity requirements, and the likelihood and impact scales those threats are scored against. Treat it as a first draft to challenge and replace with your own product's specifics before it becomes a technical file.
1. Product classification and conformity route
Article 7, Annex III, Annex IV, Article 32Product: [your product name]
Proposed classification: Default class product with digital elements, not listed in Annex III or Annex IV
Justification: A general-purpose programmable controller is not named in Annex III or Annex IV, so it is a default-class product with digital elements and follows the Article 32 self-assessment route. Where the controller is marketed specifically as a safety component or an industrial firewall, re-run the classification, since those functions are listed separately.
Conformity route: Article 32(1), internal control (self-assessment)
Standards to apply: IEC 62443-4-1; IEC 62443-4-2; IEC 61508 (where safety-related)
Decision owner: [name, role]
Decision date: [date]
Classification drives everything downstream, so settle it before writing the assessment. Check whether any component of your product is separately listed, and record who signed the decision and when. If your product is marketed with a function listed in a higher class, that class wins.
2. Asset inventory
Annex I Part I (1), Article 13(3), Annex VII| Asset | Type | Classification | Why it matters |
|---|---|---|---|
| Controller firmware | component | internal | Runtime firmware and bootloader on the controller. |
| Control logic program | data | restricted | The engineered ladder/ST program that drives plant behaviour. |
| Fieldbus interface | network | internal | PROFINET/EtherNet-IP/Modbus link to I/O and drives. |
| Engineering access function | function | restricted | Program download, forcing and online-edit capability. |
| Process setpoints | data | confidential | Operating parameters whose manipulation changes physical output. |
| Plant safety envelope | societal | restricted | The physical safety consequence of loss of control. |
| Maintenance account | user related | restricted | Integrator and maintenance identities with engineering rights. |
Assets to add: [anything specific to your architecture, such as third-party services, hardware security modules or region-specific data stores]
An asset is anything an attacker would want to reach, break or abuse. Delete rows that do not exist in your product and add the ones that make yours different, since generic inventories produce generic threats. Classify each asset by the harm its exposure would cause rather than by where it happens to be stored.
3. Threat analysis (STRIDE)
Annex I Part I (2), Article 13(2)| Threat | STRIDE | Asset | L / I | Annex I ref |
|---|---|---|---|---|
| An attacker exploits known, not fixed vulnerabilities in the product under review. | elevation of privilege | Controller firmware | high / high | ANNEX I Part I (2)(a) |
| An attacker exploits a vulnerability for which a security update is available but not installed. | elevation of privilege | Controller firmware | high / high | ANNEX I Part I (2)(c) |
| An attacker exploits a weakness in the default configuration of the product under review. | elevation of privilege | Controller firmware | high / high | ANNEX I Part I (2)(b) |
| An attacker gains unauthorized access to the product under review. | elevation of privilege | Engineering access function | high / high | ANNEX I Part I (2)(d) |
| An attacker tampers stored data in the product under review. | tampering | Control logic program | medium / high | ANNEX I Part I (2)(f) |
| An attacker tampers with data transferred to or from the product under review. | tampering | Fieldbus interface | medium / high | ANNEX I Part I (2)(f), ANNEX I Part I (2)(m) |
| An attacker impacts the availability of basic or essential functions during an incident. | denial of service | Plant safety envelope | medium / high | ANNEX I Part I (2)(h) |
| An attacker exploits a vulnerability for which no security update is available or feasible. | elevation of privilege | Controller firmware | medium / high | ANNEX I Part I (2)(c) |
| An attacker performs a security-relevant activity that is not recorded or monitored by the product under review. | repudiation | Engineering access function | medium / medium | ANNEX I Part I (2)(l) |
| An attacker exploits a vulnerability because the user was not aware an update needed to be installed. | elevation of privilege | Controller firmware | medium / high | ANNEX I Part I (2)(c) |
Each threat is tied to an asset and to an Annex I Part I essential requirement, which is what an authority will ask you to evidence. Likelihood and impact here are starting values from the CRA threat catalogue. Re-score them against your own deployment: an interface that is unreachable in your architecture is not a medium risk just because the catalogue says so.
4. Risk criteria
Annex I Part I (1), Article 13(3), Annex VII| Scale | Level | Score | Meaning |
|---|---|---|---|
| likelihood | Rare | 1 | Exceptional occurrence. Highly unlikely during the product lifecycle. |
| likelihood | Unlikely | 2 | Could occur, but only under limited circumstances or with significant effort. |
| likelihood | Possible | 3 | Realistic occurrence under credible attack conditions. |
| likelihood | Likely | 4 | Expected to occur in multiple realistic scenarios or repeated attempts. |
| likelihood | Almost Certain | 5 | Expected to occur frequently or with minimal attacker effort. |
| impact | Negligible | 1 | Minimal operational disruption and no meaningful cybersecurity consequence. |
| impact | Minor | 2 | Limited disruption or localized loss with low recovery effort. |
| impact | Moderate | 3 | Noticeable service disruption, data exposure, or recovery effort requiring management attention. |
| impact | Major | 4 | Severe business disruption, major data compromise, or significant recovery cost. |
| impact | Catastrophic | 5 | Critical operational failure, widespread compromise, safety implications, or major regulatory impact. |
Document the scales before you score anything, otherwise the scoring is unfalsifiable. These are the default five-by-five scales. Adjust the wording so it reflects consequences your organisation actually recognises, and state your risk acceptance threshold explicitly.
5. Risk treatment and mitigations
Annex I Part I (2), Article 13(1)- Controller firmware: Address known exploitable vulnerabilities before release and maintain an effective vulnerability management process.
- Controller firmware: Ensure timely deployment of security updates and monitor update compliance.
- Controller firmware: Harden default settings, minimise enabled services, and require secure initial configuration.
- Engineering access function: Require authenticated engineering sessions and a physical key-switch or equivalent for program download in run mode.
- Control logic program: Sign and integrity-check the control program so an altered download is detected before execution.
- Fieldbus interface: Authenticate control traffic or segment the fieldbus so injected frames cannot reach drives.
- Plant safety envelope: Define and test the controller's safe state on network loss or CPU overload.
- Controller firmware: Document compensating controls for the long plant lifetime where patching windows are rare.
- Engineering access function: Log and monitor security-relevant events by default and protect monitoring evidence.
- Controller firmware: Notify users about updates and support automatic or guided secure update installation.
For each risk, record: treatment (accept / mitigate / transfer / avoid), the control that implements it, the residual score after treatment, and the owner.
Accepted risks: [list, with the justification and who accepted them]
A mitigation that is not implemented is not a mitigation. Point each line at a real control, a configuration default or a design decision you can evidence. Accepted risks are legitimate, but they need a named accepter and a reason that survives scrutiny.
6. Vulnerability handling and reporting readiness
Annex I Part II, Article 13(8), Article 14Coordinated vulnerability disclosure contact: [security.txt URL, security contact]
Support period: [end date, per Article 13(8)]
SBOM: [format, where it is maintained]
Article 14 reporting: actively exploited vulnerabilities and severe incidents are reported to ENISA and the CSIRT within 24 hours (early warning) and 72 hours (notification).
Named responsible person: [name, role]
The risk assessment is one half of Annex I. Part II obligations run for the whole support period, so the reporting path has to exist before you place the product on the market, ready ahead of your first exploited vulnerability.
Start this assessment in CVD Portal
Create the product and CVD Portal pre-fills this asset inventory, the matching STRIDE threats and your risk criteria, ready to review and adjust.
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