Hardware trojans - which involve malicious modification of integrated circuits (ICs) during the design or fabrication stage - can give access to sensitive information, deny service, and so on. They can be difficult to detect but have serious consequences for the security of the IC. Exploring hardware trojan attacks and their countermeasures using high level synthesis (HLS), this book covers different attack strategies, their detection and countermeasures, as well as future risks. The expert author presents key information on hardware trojan attacks and their countermeasures. The book is split into four parts, starting with an introduction to hardware trojans and high-level synthesis, and then looking at various attack strategies. This is then followed by information on detection (a key issue in hardware trojan security), and countermeasures. The book finishes by looking at additional concerns and future directions of this key area in hardware security. Readers will learn about topics such as hardware trojan classification and taxonomy, trojan attacks using malicious HLS framework, time bomb HLS-based hardware trojan attacks, trojan attacks on ML accelerator designs, other payloads of HLS trojan attack, trojan detection technique using DMR, and trojan detection and isolation technique and compromising IP designs via malicious exploitation of commercial CAD-HLS tools. High-Level Synthesis Hardware Trojan Attacks and Countermeasures is a key resource for researchers and engineers working in hardware security and chip design.