Fabless semiconductor companies design system-on-chips (SoC) by using third-party intellectual property (IP) cores and fabricate them in offshore, potentially untrustworthy foundries. Owing to the globally distributed electronics supply chain, security has emerged as a serious concern. In this article, we explore electronics computer-aided design (CAD) software as a threat vector that can be exploited to introduce vulnerabilities into the SoC. We show that all electronics CAD tools—high-level synthesis, logic synthesis, physical design, verification, test, and post-silicon validation—are potential threat vectors to different degrees. We have demonstrated CAD-based attacks on several benchmarks, including the commercial ARM Cortex M0 processor [1].