Hardware ProtectionProtecting Hardware from Software Attacks

Published 23 October 2021

In order to break the endless cycle of software patch-and-pray, DARPA’s System Security Integration Through Hardware and firmware (SSITH) program aims to develop ASIC hardware with novel protections proven in mitigating against software attacks on hardware.


DARPA’s System Security Integration Through Hardware and firmware (SSITH) program is exploring hardware security architectures and tools that protect electronic systems against common classes of hardware vulnerabilities exploited through software, with the goal of breaking the endless cycle of software patch-and-pray. To date, research on the program has focused on developing approaches and proving out concept that system-on-chip (SoC) designers can use to limit computer hardware to states that are secure while maintaining performance and power.

After rigorous testing and evaluation, researchers have proven that SSITH concepts provide robust hardware safeguards against known common weakness enumeration (CWE) classes of hardware vulnerabilities. The SSITH program is now entering a final stage and is focused on transitioning and converting the proven concepts from lab discoveries to practical application. The team from Lockheed Martin Corporation is moving beyond virtual processors and aims to develop an application-specific integrated circuit (ASIC) that integrates a dual-core Arm processor and multiple peripheral interfaces with embedded security capabilities provided by their proven SSITH approach, known as Hardware Architecture Resilience by Design (HARD).

Lockheed Martin’s HARD utilizes an approach to provide a hardware solution to protect systems against multiple classes of hardware vulnerabilities. Rather than perform “major surgery” on the CPU pipeline in order to implement new instructions or change the format of a pointer, the HARD approach utilizes a set of pipelines running in parallel to the primary CPU execution pathway to act as a parallel security co-processor, monitoring the main CPU and standing ready to flag any malicious operations. Each pipeline monitors the stream of instructions executing on the main CPU pipeline, deriving the current semantic context based on expected patterns of instructions, and looking for any exploitation attempts.

HARD pipelines can be aggregated to deploy more or less security coverage as needed for the target environment, essentially enabling a user to only pay for what they need. In addition, because there is no need for major modifications to the primary CPU, HARD can be deployed to enforce security across any CPU architecture.

“By bringing HARD protections to an ASIC, we’re bringing SSITH technology one step closer to practical use,” said Keith Rebello, the program manager leading SSITH. “Lockheed Martin expects to spend the next two years transitioning HARD from the laboratory to a secure processor that we can integrate with other computing hardware, ultimately demonstrating SSITH’s ability to protect real-world systems from exploitation.”