Security: interview prep

Interview questions

Key points for each answer are in the app's question bank.

1. Explain a secure boot chain from ROM to application.Intermediate
2. Signing versus encrypting firmware: what does each protect against?Basic
3. Where should device keys be stored?Intermediate
4. What does TrustZone for Cortex-M provide?Intermediate
5. What is anti-rollback protection?Intermediate
6. How do you lock down debug access on production devices?Intermediate
7. Why must MAC or password comparisons be constant time?Advanced
8. How can firmware defend against buffer overflows?Intermediate
9. Is TLS practical on a microcontroller? What does it cost?Intermediate
10. Why do you need a true random number generator in firmware?Intermediate
11. Design a secure OTA update for a connected product.Advanced
12. What does readout protection do, and what doesn't it stop?Basic

Hands-on challenges

Design rounds

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