NDSU researchers discover hidden chip threats and a way to stop them

Every day, billions of people trust computer chips to protect their most sensitive information, ranging from banking passwords to national security secrets. But what if those chips were secretly compromised before they even left the factory?

Researchers at NDSU and Southern Illinois University Edwardsville have discovered a new class of hidden chip threats, called hardware Trojans, that can silently steal confidential data while completely evading every existing security check. More importantly, the team has developed a groundbreaking method to detect these threats and stop them in their tracks.

"We live in a world where the chips inside our devices are designed and manufactured across multiple countries and companies," said Kushal Ponugoti, a faculty member in NDSU’s Department of Electrical and Computer Engineering. "That complexity creates opportunities for bad actors to hide malicious components deep inside the hardware.”

The collaborative research focuses on a specialized computer chip design called Pre-Charge Half Buffer asynchronous circuits. Because these chips can operate reliably under extreme conditions, they are increasingly used in high-stakes environments such as space exploration, automotive electronics, and military systems.

However, the research team, which includes NDSU graduate student Chukwunalu Asuai, investigated how malicious actors could secretly embed harmful components into these chips to steal sensitive information, like private encryption keys, while appearing completely normal during routine security checks.

The researchers designed three new types of hardware Trojans specific to PCHB circuits:

• DATA0-Trojan
• DATA1-Trojan
• MUX-Trojan

These Trojans exploit a subtle loophole in the way PCHB chips handle data. They remain completely dormant and undetectable during normal operation, but spring into action when triggered by a specially crafted, abnormal input. Because these Trojans introduce negligible hardware overhead, they are nearly impossible to spot through physical inspection alone.

To counter these threats, the team developed formal mathematical verification techniques that systematically examine chip designs for signs of these hidden Trojans. The methods were tested on 28 chip designs of varying sizes, including large-scale encryption circuits up to 2048 bits, and successfully detected all hidden Trojans with 100% accuracy.

Crucially, this detection works at the design stage before the chips are manufactured. This makes the solution far more cost-effective than trying to catch problems after production.

The full study has been published in the IEEE Xplore digital library and can be accessed via the IEEE Journal Article Link.

“What makes these Trojans particularly dangerous is that they look completely innocent under every existing security test, only revealing themselves under very specific abnormal conditions that a malicious actor can deliberately trigger,” Ponugoti said. “Our work shows not only that these threats are real and practical, but also that we now have the tools to find them before they cause harm."

The researchers note that the growing complexity of global chip supply chains means hardware security can no longer be treated as an afterthought. This study serves as a wake-up call for the semiconductor industry, government agencies, and defense organizations that rely on these chips for mission-critical applications.

As artificial intelligence continues to accelerate chip design processes, the risk of sophisticated and covert Trojan insertion will only grow, making proactive formal verification essential for safeguarding modern tech infrastructure.

The team recommends that chip designers and hardware security engineers begin incorporating formal verification techniques that account for illegal input conditions into their standard validation processes.

Looking to the future, the NDSU and SIUE research team plans to expand on this breakthrough by extending their detection strategies to even more complex, sequential PCHB chip designs. To ensure these findings have a widespread practical impact, the researchers aim to integrate their automated detection tools directly into existing industrial workflows, making the defensive technology easily accessible to chip designers worldwide. Additionally, the team will investigate how other traditional hardware threats might be adapted into asynchronous circuits, staying one step ahead of bad actors to ensure the hardware underpinning modern society remains secure and trusted.