Cybersecurity Hardening

Embedded Linux Security Hardening for Embedded Systems

Secure Your Embedded Devices from Day One

Today’s connected devices face growing threats — from IP theft and data breaches to firmware tampering and supply chain attacks. Whether you develop automotive, industrial, medical, or consumer-grade electronics, hardening your embedded system against cyber risks is no longer optional. Security challenges for any embedded system continue to evolve, requiring constant vigilance and robust protection measures.

At Promwad, we provide embedded cybersecurity engineering services to help you secure your devices across the full lifecycle — from initial design to post-deployment support. Our approach leverages linux security best practices as part of a comprehensive strategy, tailored to your industry standards and regulatory landscape.

Our Cybersecurity Hardening Services

We offer a full suite of services to protect your embedded systems:

Secure Boot & RoT

Hardware-based Secure Boot chains, including trusted execution environment options for secure code and data isolation
ARM TrustZone, TPM, HSM, and Secure Elements
Key provisioning and anti-cloning protection
Verification of the kernel image and linux kernel image as part of the secure boot process to ensure integrity and authenticity

Encrypted Firmware and OTA Updates

We help you keep firmware and software packages up to date to patch vulnerabilities and maintain system security.

AES-256/GCM firmware encryption
Secure key management and rotation
Failsafe OTA update workflows with rollback support

Runtime Secutity

MPU/MPMMU configuration for memory segmentation
Stack overflow detection and runtime integrity checks
Application sandboxing (e.g., OP-TEE, SELinux)

Device Identity and Authentication

We implement secure authentication using cryptographic keys, including private key and public key pairs, to ensure device identity and prevent unauthorised access.

X.509 certificates and mutual TLS
Secure device provisioning at scale
Unique hardware-bound credentials

Threat Modelling and Risk Assessment

STRIDE, DREAD, and PASTA methodologies
Industry-specific threat surface analysis
Security posture audits for existing firmware

Compliance

ETSI EN 303 645 (consumer IoT)
NIST 8259A (US federal IoT security)
ISO 21434 (automotive), IEC 62443 (industrial), IEC 62304 (medical)

Secure your embedded device with Promwad!

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When Do You Need Cybersecurity Hardening?

We adapt hardening techniques and security configurations to your architecture and specific target system, taking into account the operational environment—whether it’s ARM Cortex-M, RISC-V, or complex SoCs running embedded Linux. Explore the use cases we support:

Automotive ECUs and gateways

Security risks assessed: Remote code injection, CAN bus spoofing
Implementing strong network security measures is essential to protect automotive ECUs and gateways, including configuring appropriate firewall rules to help mitigate the risk of remote code injection.

Medical wearables and health monitors

Security risks assessed: Patient data leaks, unauthorised updates
To mitigate these risks, it is recommended to use full disk encryption to encrypt data stored on block devices, ensuring that patient information remains protected even if the storage media is compromised.

Smart home and consumer IoT

Security risks assessed: Privacy violations, botnet participation
Attackers may exploit specific attack vectors, such as botnets or vulnerabilities in device software, to gain access to smart home devices and compromise user privacy.

Industrial controllers and IIoT devices

Security risks assessed: Factory malware, PLC hijacking, data exfiltration
To further mitigate these risks, industrial systems can use external devices such as Secure Elements or TPMs for secure key storage, and implement an additional layer of security like SELinux or AppArmor to enforce security policies.

Embedded Linux or RTOS-based systems

Security risks assessed: Root exploits, privilege escalation, firmware backdoors
To mitigate these risks, it is essential to restrict user privileges, secure user space interactions, and closely monitor kernel module loading, as these measures help prevent privilege escalation, block unauthorised access, and protect against firmware backdoors.

Our Methodology

Our team integrates security engineering into your development flow — from early prototyping to release. We incorporate robust security mechanisms, drawing on best practices from linux servers and other operating systems, to ensure comprehensive protection throughout the development lifecycle.

Requirements Definition

System Architecture Review

Implementation & Integration

Verification, Secure Boot & Penetration Testing

Lifecycle Security Planning

Kernel Configuration and Modules

Securing an embedded Linux system starts at the kernel level. The Linux kernel offers a wide array of security features that can be fine-tuned during the kernel configuration process. Enabling Mandatory Access Control (MAC) frameworks, such as SELinux or AppArmor, allows you to enforce strict access control policies, limiting how applications and users can access resources on your device. Careful selection and configuration of kernel modules are equally important—only essential modules for networking, file systems, or cryptographic operations should be enabled. This approach minimises the attack surface and reduces the risk of exploitation.

Loadable kernel modules, while providing flexibility, can introduce vulnerabilities if not properly managed. To prevent unauthorised modifications, it’s crucial to implement secure module loading practices, such as module signing, which ensures that only trusted kernel modules are loaded into the system. By rigorously managing kernel configuration and module loading, you can significantly strengthen the security posture of your embedded Linux device and guard against a wide range of attack vectors.

Physical Security and Protection

While software security is vital, physical security is just as critical for embedded Linux systems. If an attacker gains physical access to your device, they may attempt to extract sensitive data or install malicious software. To counter these risks, implementing secure boot mechanisms—such as UEFI Secure Boot or leveraging a Trusted Platform Module (TPM)—ensures that only authorised firmware and software can run on your hardware.

Monitoring and Maintenance

Ongoing monitoring and maintenance are essential for effectively defending embedded Linux systems against constantly evolving cyber threats. By continuously observing system behavior and analysing network traffic, you can quickly detect signs of security threats, such as unauthorised access attempts or suspicious activity. utilising standard tools like intrusion detection systems and log analysers enables proactive threat detection and response.

Incident Response and
Recovery

An effective security strategy requires a clear incident response and recovery plan. In the event of a security incident—such as a data breach or unauthorised access—having clear procedures for containment, eradication, and recovery is vital. Secure network communications play a key role during incident response, helping to prevent the spread of malicious activity and maintain response integrity.

Compliance and Regulatory Requirements

Meeting compliance and regulatory requirements is a fundamental aspect of embedded Linux system security, especially when handling sensitive data. Regulations such as GDPR and HIPAA demand robust security measures, including strict access control models like discretionary access control and mandatory access control, to ensure that only authorised users can access protected information.

Why Choose Promwad?

We work as part of your engineering team — ensuring compliance, protection, and long-term security posture for every release.

Cross-industry experience

From IEC 61508 PLCs to ISO 21434 automotive gateways

Trusted technologies

PSA Certified, TUF, WolfSSL, mbedTLS

Flexible delivery models

Security consulting, full integration, or long-term support

Partnerships with leading vendors

Collaboration with chip vendors and security labs across the EU

Let’s secure your firmware, data, and infrastructure — starting now.

Drop us a line about your project! We will contact you today or the next business day. All submitted information will be kept confidential.