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Security by Design
Definition
Security by Design is a design principle where security is built into systems, software, and processes from the start — rather than added as an afterthought. The EU Cyber Resilience Act mandates this.
Security by Design is a design principle where security is built into systems, software and processes from the start rather than added as an afterthought. The EU Cyber Resilience Act (CRA) makes Security by Design legally mandatory for all products with digital elements on the European market.
How does Security by Design work?
Security by Design integrates security into every phase of the development cycle. In the design phase, threat modeling identifies potential threats before any code is written. Security requirements are included as functional requirements. The attack surface is minimised by eliminating unnecessary functionality. Secure defaults are applied. The fail-secure principle ensures systems default to a safe state upon failure.
Security by Design versus Security by Default
Security by Design focuses on the design process. Security by Default focuses on the end user: the product is securely configured by default. Both are complementary and mandated by the CRA.
Impact on organisations
The CRA introduces mandatory Security by Design requirements for all digital products on the EU market. Non-compliant manufacturers risk fines up to 15 million euros. GDPR requires Privacy by Design. NIS2 requires security measures reflecting the current threat environment. Organisations applying Security by Design significantly reduce production vulnerabilities and lower remediation costs.
Protection
Integrate threat modeling into the design process. Apply secure coding standards. Implement automated security testing in CI/CD pipelines. Conduct regular code reviews and pentests. Minimise the attack surface.
How DEFION helps
DEFION provides Secure Development Training and Code Security Reviews evaluating Security by Design principles. The CRA Readiness Assessment evaluates product compliance with CRA requirements.