Annex III, Class II (4)
Tamper-resistant microcontrollers
Tamper-resistant MCUs are important product, class ii under Regulation (EU) 2024/2847 when the listed function is the product's core functionality. As for tamper-resistant microprocessors: the product's value is its resistance to attack, so its conformity must be independently assessed.
Updated 2026-09-12 · Operational guidance, not legal advice.
- Classification
- Important product — Class II
- Conformity route
- Third-party assessment required
- Reference
- Annex III, Class II (4) · Art. 32(3)
What the annex says
Tamper-resistant microcontrollers.
Paraphrase of Annex III, Class II (4); the Official Journal text governs.
Typical products in this category
- Secure MCUs with active shielding and tamper response
- Authentication ICs for accessories and consumables
Where the boundary runs
Microcontrollers with security-related functionality but without tamper resistance are Class I.
The test is core functionality (Article 7). Record the reasoning and the approver: the category determines the conformity assessment route and market surveillance authorities can challenge it.
Conformity assessment
Third-party assessment required. EU-type examination (Module B) with conformity to type (Module C), or full quality assurance (Module H), involving a notified body; alternatively a European cybersecurity certificate at assurance level 'substantial' or higher where a scheme exists. (Art. 32(3))
What to prepare operationally
- Keep the firmware and SDK SBOMs alongside the hardware documentation.
- Define how a field-discovered weakness in tamper response is remediated or communicated when a firmware update cannot fix it.
- Publish part-number-level applicability in advisories.
- Maintain an SBOM per released version, match it continuously against vulnerability intelligence, and keep the Article 14 runbook rehearsed — these apply to every product with digital elements, listed or not.
Frequently asked
- Is every tamper-resistant mcus product an important product — class ii?
- Only where the listed function is the product's core functionality (Article 7). Microcontrollers with security-related functionality but without tamper resistance are Class I.
- What changes compared with a default product?
- EU-type examination (Module B) with conformity to type (Module C), or full quality assurance (Module H), involving a notified body; alternatively a European cybersecurity certificate at assurance level 'substantial' or higher where a scheme exists. The essential requirements of Annex I, the vulnerability-handling duties and Article 14 reporting apply to every product with digital elements regardless of category.
- From when?
- Article 14 reporting obligations have applied to all manufacturers since 11 September 2026. Conformity assessment and CE marking under the CRA apply from 11 December 2027; products placed on the market before that date are not required to be re-assessed unless substantially modified.