Hardware security: Emerging attacks and protection mechanisms
Maggie Jauregui’s introduction to hardware security is a fun story: she figured out how to spark, smoke, and permanently disable GFCI (Ground Fault Circuit Interrupter – the two button protections on plugs/sockets that prevent you from electrocuting yourself by accident with your hair dryer) wirelessly with a walkie talkie.
“I could also do this across walls with a directional antenna, and this also worked on AFCI’s (Arc Fault Circuit Interrupts – part of the circuit breaker box in your garage), which meant you could drive by someone’s home and potentially turn off their lights,” she told Help Net Security.
Jauregui says she’s always been interested in hardware. She started out as an electrical engineering major but switched to computer science halfway through university, and ultimately applied to be an Intel intern in Mexico.
“After attending my first hackathon — where I actually met my husband — I’ve continued to explore my love for all things hardware, firmware, and security to this day, and have been a part of various research teams at Intel ever since,” she added. She’s currently a security researcher for Intel’s PSG (Programmable Solutions Group) organization.
What do we talk about when we talk about hardware security?
Computer systems – a category that these days includes everything from phones and laptops to wireless thermostats and other “smart” home appliances – are a combination of many hardware components (a processor, memory, i/o peripherals, etc.) that together with firmware and software are capable of delivering services and enabling the connected data centric world we live in.
Hardware-based security typically refers to the defenses that help protect against vulnerabilities targeting these devices, and it’s main focus it to make sure that the different hardware components working together are architected, implemented, and configured correctly.
“Hardware can sometimes be considered its own level of security because it often requires physical presence in order to access or modify specific fuses, jumpers, locks, etc,” Jauregui explained. This is why hardware is also used as a root of trust.
Hardware security challenges
But every hardware device has firmware – a tempting attack vector for many hackers. And though the industry has been making advancements in firmware security solutions, many organizations are still challenged by it and don’t know how to adequately protect their systems and data, she says.
She advises IT security specialists to be aware of firmware’s importance as an asset to their organization’s threat model, to make sure that the firmware on company devices is consistently updated, and to set up automated security validation tools that can scan for configuration anomalies within their platform and evaluate security-sensitive bits within their firmware.
“Additionally, Confidential Computing has emerged as a key strategy for helping to secure data in use,” she noted. “It uses hardware memory protections to better isolate sensitive data payloads. This represents a fundamental shift in how computation is done at the hardware level and will change how vendors can structure their application programs.”
Finally, the COVID-19 pandemic has somewhat disrupted the hardware supply chain and has brought to the fore another challenge.
“Because a computing system is typically composed of multiple components from different manufacturers, each with its own level of scrutiny in relation to potential supply chain attacks, it’s challenging to verify the integrity across all stages of its lifecycle,” Jauregui explained.
“This is why it is critical for companies to work together on a validation and attestation solution for hardware and firmware that can be conducted prior to integration into a larger system. If the industry as a whole comes together, we can create more measures to help protect a product through its entire lifecycle.”
Achieving security in low-end systems on chips
The proliferation of Internet of Things devices and embedded systems and our reliance on them should make the security of these systems extremely important.
As they commonly rely on systems on chips (SoCs) – integrated circuits that consolidate the components of a computer or other electronic system on a single microchip – securing these devices is a different proposition than securing “classic” computer systems, especially if they rely on low-end SoCs.
Jauregui says that there is no single blanket solution approach to implement security of embedded systems, and that while some of the general hardware security recommendations apply, many do not.
“I highly recommend readers to check out the book Demystifying Internet of Things Security written by Intel scientists and Principal Engineers. It’s an in depth look at the threat model, secure boot, chain of trust, and the SW stack leading up to defense-in-depth for embedded systems. It also examines the different security building blocks available in Intel Architecture (IA) based IoT platforms and breaks down some the misconceptions of the Internet of Things,” she added.
“This book explores the challenges to secure these devices and provides suggestions to make them more immune to different threats originating from within and outside the network.”
For those security professionals who are interested in specializing in hardware security, she advises being curious about how things work and doing research, following folks doing interesting things on Twitter and asking them things, and watching hardware security conference talks and trying to reproduce the issues.
“Learn by doing. And if you want someone to lead you through it, go take a class! I recommend hardware security classes by Joe FitzPatrick and Joe Grand, as they are brilliant hardware researchers and excellent teachers,” she concluded.