Hardware threats might seem distant to software developers. However, attacks are increasingly no longer limited to vulnerabilities in code. Cybercriminals exploit weaknesses at the level of processors, integrated circuits, or communication systems to gain access to sensitive data or take access control of devices. Hardware security is no longer limited to design and auditing. So how can we defend against such threats? Building on our hardware security fundamentals guide, this article aims to present the most important security challenges of hardware systems. We will also discuss how attacks can exploit the physical aspects of hardware to bypass security measures and what strategies can help mitigate them.
Unlike traditional attack methods that directly compromise software-based or system logic, these attacks exploit the physical properties of hardware operation, such as power consumption, electromagnetic radiation, execution time, or intentional fault injection. Such attacks can lead to the disclosure of sensitive information or the takeover of devices without the need to breach their internal security measures directly. As Bruce Schneier, a renowned security expert, has said: "As hardware becomes cheaper and smaller, attacks become more feasible. It’s no longer just about software vulnerabilities; hardware attacks are the next frontier in cyber warfare".
Side-channel attacks exploit data derived from the physical aspects of hardware operation, such as power consumption, electromagnetic radiation, or execution time, to gain access to sensitive information like cryptographic keys. These attacks are difficult to detect because they do not directly compromise system integrity but instead gather data from the system's behavior. Attackers can analyze differences in power usage, measure radiation emitted by the device, or even monitor the execution time of specific operations to extract critical information.
This kind of attack involves deliberately introducing errors into a system by manipulating the physical properties of the hardware devices, such as voltage, temperature, or laser exposure. These attacks can disrupt the operation of circuits, potentially leading to the execution of unauthorized code or access to protected data.
Deepen your knowledge of hardware design and engineering.
Side-channel leakage, exposed debug ports and unauthenticated buses are design decisions, not accidents. Our electronics engineers audit your schematic and board layout and tell you which attack paths are actually reachable in your product.
Review your hardware attack surface
Firmware, such as BIOS, UEFI, or the software of peripheral devices (e.g., network cards or SSDs), is an extremely attractive target for cybercriminals. Due to its low-level operation, attacks on firmware are difficult to detect. Moreover, malware installed at the firmware level can survive even a reinstallation of the operating system, making such attacks particularly dangerous. Therefore, it is worth giving them more attention.
Attacks on firmware can be carried out in several ways:
Solution: Protection against firmware attacks requires the implementation of several mechanisms:
Firmware updates are crucial for maintaining a layer of security, as many vulnerabilities are exploited by attackers at the firmware level. The update process itself can be a target of man-in-the-middle (MITM) attacks if not properly secured. Additionally, many older devices stop receiving updates, leaving them vulnerable to attacks.
Solution: To ensure secure firmware updates, several principles should be followed:
DDoS attacks involve overwhelming a system with an enormous amount of network traffic, which overloads the infrastructure and prevents the system from functioning normally. These attacks are relatively easy to execute, especially using botnets, which can consist of thousands of infected devices distributed worldwide. Attackers use these botnets to generate large amounts of fake network traffic, overloading server resources, network services, or web applications.
Example: In 2016, a DDoS attack on Dyn, a DNS service provider, caused temporary downtime for many popular websites, including Twitter, Spotify, Reddit, and others. The attack was made possible by the Mirai botnet, which infected IoT devices and used them to generate network traffic.
Solution:
Modern networks, such as the Internet of Things (IoT), are characterized by a distributed topology and multiple access points, which increases the risk of interception or loss of cryptographic keys. These keys, which form the foundation of data transmission security, are particularly vulnerable to attacks during their transfer between systems, applications, or users.
One of the key challenges is generating secure cryptographic keys. Weaknesses in key generation can lead to predictability, ultimately allowing security to be compromised. Poorly designed random number generators, especially in resource-constrained systems, can result in the use of low-entropy keys, increasing vulnerability.
Solution: InTechHouse recommends utilization of high-entropy random number generators, based on physical or cryptographic sources. Dedicated hardware modules such as Hardware Security Modules (HSM) and Trusted Platform Modules (TPM) provide a secure environment for generating and storing keys. In 2023, the HSM market reached a value of approximately USD 1.5 billion, and forecasts indicate that by 2033 its value will grow to USD 5.9 billion, with an annual growth rate of 16.5%. Cryptographic systems can also benefit from using CSPRNGs (Cryptographically Secure Pseudo-Random Number Generators), which ensure unpredictable keys.
Moreover, the transmission of cryptographic keys between systems, applications, or users is a critical point where keys are most vulnerable to interception. In distributed networks, complex topology and numerous access points increase the risk of key leakage.
Solution: Key distribution should always be carried out using secure protocols such as TLS (Transport Layer Security) or IPsec, which provide both encryption of the transmission and authentication of the parties involved. Symmetric keys should be transmitted in encrypted form using asymmetric keys within key exchange protocols, such as Diffie-Hellman or ECDH (Elliptic Curve Diffie-Hellman). In distributed systems, implementing centralized key management systems, such as KMS (Key Management Service), is advisable to automate key distribution and rotation across the entire environment.
Subsequently, the microarchitecture of processors, responsible for the internal organization and optimization of CPU operations, plays a significant role in ensuring the performance of computer systems. However, it is increasingly becoming a target for attacks that exploit advanced techniques, such as speculative execution and cache management, to gain access to protected data.
The Spectre and Meltdown attacks revealed vulnerabilities related to CPU performance optimization mechanisms, such as speculative execution and caching. Speculative execution allows processors to predict future instructions to enhance execution speed, but these predictions can lead to data leaks that would otherwise be protected by isolation mechanisms. Meltdown, in particular, enables unauthorized access to kernel memory, potentially leading to the exposure of sensitive information.
Retrofitting tamper resistance after tape-out is expensive. We build secure element integration, protected debug access and hardened power rails into the design from the first schematic review.
Not sure where to start? We work with companies at every stage, from early ideas to enterprise-level builds. A 30-minute call can save you months of guesswork.
A secure element, a TPM and an HSM all protect cryptographic keys in tamper-resistant hardware, but at different scales. A secure element is a small certified chip on the device board, used for device identity and authentication in IoT products. A TPM is a crypto processor standardized by the Trusted Computing Group, common in PCs and gateways for measured boot and key storage. An HSM is a server-side appliance or cloud service protecting high-value keys, such as firmware signing keys.
JTAG and SWD debug ports should be locked or disabled on production devices, because an open port gives direct access to memory, flash contents and keys. Most microcontrollers provide readout protection levels or debug-disable fuses, and many support authenticated debug so authorized engineers can still reopen access to a unit for failure analysis. Removing the header is not enough, since test pads remain reachable. The lock state should be verified for every unit during end-of-line testing.
Secure boot creates a hardware root of trust by starting execution from immutable code, usually boot ROM, which verifies the digital signature of the next boot stage before running it. The public key or its hash is stored in one-time programmable fuses, so an attacker cannot replace it. Each stage then verifies the next, forming a chain of trust up to the application. Anti-rollback counters prevent reinstalling older signed firmware with known vulnerabilities.
Fault injection attacks such as voltage or clock glitching are mitigated by detecting abnormal operating conditions and making a single fault insufficient to bypass security. At chip level this means voltage, clock and temperature monitors that reset the device, and secure elements with active shielding. In firmware, critical checks are duplicated, comparisons use values that a single bit flip cannot produce, and random delays reduce timing precision. Board design helps by filtering supplies and removing unnecessary access to core voltage rails.
Security requirements for connected hardware come from several standards, depending on the market. ETSI EN 303 645 sets baseline requirements for consumer IoT devices, IEC 62443-4-2 defines component security levels for industrial automation, and FIPS 140-3 covers cryptographic modules for US government use. In the EU, the Cyber Resilience Act makes security by design, vulnerability handling and security updates mandatory for products with digital elements, which affects hardware choices such as secure boot and update capacity.
Krzysztof Niedźwiedź is a Lead Embedded Systems and Hardware Engineer at InTechHouse with over 11 years of experience developing complex electronic and embedded products from system architecture through production.
He specializes in embedded software development, electronic system architecture, multilayer PCB design, hardware-software integration, system testing, and technical ownership of high-reliability engineering projects. His work spans requirements analysis, architecture and component selection, schematic and PCB design, bare-metal and RTOS firmware development, prototyping, troubleshooting, production documentation, and cooperation with mechanical and high-level software teams.
Krzysztof's project experience includes FPGA and SoC-based onboard computers for the space industry, embedded electronics for advanced optical equipment, low-power environmental-monitoring devices, UAV payloads for real-time air-quality measurement and sample collection, and connected medical and training devices.
He works with C and C++, STM32, LPC and AVR microcontrollers, ARM-based platforms, RTOS, Embedded Linux, FPGA and SoC architectures, DDR3, HDI PCB technology, and industrial communication interfaces including Ethernet, CAN, RS-485, SPI, I2C, UART, USB, Modbus, and MQTT.
Krzysztof holds bachelor's and master's degrees in Electronics and Telecommunications. He is an IPC Certified Interconnect Designer and has completed specialist training in Embedded GNU/Linux kernel internals and device drivers. He writes about embedded system architecture, firmware development, PCB design, MCU and FPGA integration, RTOS, hardware security, low-power electronics, and dependable electronic products.
From first prototype to production, our engineers can help you scope it, build it and get it certified.
This initial conversation is focused on understanding your product, technical challenges, and constraints.
No sales pitch - just a practical discussion with experienced engineers.
Share a few details about your product and context. We’ll review the information and suggest the most appropriate next step.
