With the new Cyber Resilience Act coming into effect, our enterprise needs to harden our IoT infrastructure. Most of our sensors are "headless"—they have no user interface and limited CPU. We can't install antivirus or EDR. How do we implement Zero Trust (never trust, always verify) for these devices? What is the role of Micro-segmentation and Device Attestation in preventing an attacker from using a smart thermostat to pivot into our core database?
3 answers
For headless devices, Zero Trust must happen at the network and gateway layers. Use Micro-segmentation to isolate each device class into its own VLAN. A smart camera should only be able to talk to the NVR (Network Video Recorder), never the HR database. Device Attestation ensures that only devices with a valid, hardware-backed identity (like a TPM or Secure Element) can join the network.
What about "Identity for Things"? Can we use PKI (Public Key Infrastructure) to give every sensor a unique certificate, and does that satisfy the requirement for continuous verification in a Zero Trust model?
Focus on the Software Bill of Materials (SBOM). Knowing exactly what code is running on your IoT devices allows you to proactively patch vulnerabilities before they are exploited. Zero Trust is as much about knowing your inventory as it is about locking doors.
Agreed. You can't secure what you can't see. An automated asset discovery tool is the "Step 0" of any IoT Security strategy.
Yes, PKI is the backbone of IoT identity. However, "continuous verification" also requires monitoring behavioral anomalies. If a sensor usually sends 1KB of data per hour but suddenly starts sending 100MB to an external IP, your Zero Trust controller should automatically revoke its certificate and kill the connection, regardless of its "identity."