IoT Device Security: Risks, Best Practices, and Protection Tips

IoT device security (otherwise known as connected product security) refers to the policies, tech, and practices designed to protect Internet-connected devices from cyber threats and unauthorized access. Several pieces of state and federal legislation in the US have tried to require stronger security and cryptographic standards across the IoT domain.

IoT device security is not as straightforward as traditional IT infrastructure security. IoT devices often have limited hardware and computing capabilities, which increases their vulnerability to attack. In industrial (and similar) environments, IoT often overlaps with operational technology (OT), as IoT devices are deployed in safety-critical roles. If one of those devices is compromised, it could spell disaster for critical infrastructure and the people working in those environments.

Authentication, encryption, secure firmware updates, and continuous monitoring are key to IoT PKI and firmware security for your organization.

The Internet of Things suffers from security as a reactionary measure, not proactive to prevent attacks in the first place. However, the same technologies that are protecting cloud-based systems today (such as PKI) can be applied to IoT security.

There are about 30 billion connected devices in 2025, and that number is expected to rise to hundreds of billions by 2040. More recent estimates expect 40-42 billion IoT devices in the next year alone. Despite discrepancies in estimates, the message is clear: the volume, velocity, and criticality of IoT devices is growing at an accelerating pace.

This growth will be driven not only by consumer demand but also by smart cities, industrial automation, connected healthcare, and autonomous systems.

However, many existing consumer and enterprise devices still lack built-in security, making them easy targets for hackers. Product security teams face growing complexity in managing the lifecycle of IoT credentials, firmware, and cryptographic keys across device fleets.Without scalable, future-ready security architectures, organizations risk losing control of the very infrastructure they depend on. 

Cybercriminals exploit IoT security vulnerabilities such as:

• Weak authentication: Default, weak, or easily guessed passwords, as well as a lack of multi-factor authentication. For example, many internet routers used to use the same hard-coded admin credentials and upgraded to randomized passwords, but both are a security risk if they remain unchanged by the consumer.
• Unpatched firmware: Manufacturers failing to provide timely updates for discovered security risks to keep IoT devices aligned with the newest security standards.
• Insecure APIs: Poorly secured communication channels between devices and cloud services, which can give hackers easy access to private data or the device itself.
• Lack of encryption: IoT devices can sometimes transmit data in plain text, meaning anyone who gains access to the data can read it. When you consider how many IoT devices track users’ vital health information (such as fitness watches), this vulnerability becomes even more dangerous.
• Insufficient network security: Connected devices often communicate over unsecured Wi-Fi or cellular networks. These networks provide attackers easy access to potentially sensitive or private data.
• Over-the-air (OTA) update misconfigurations: Poorly implemented OTA updates can open devices to remote code execution or bricking.

These flaws remain top targets in connected device security threats today. Hardcoded credentials, lack of device identity validation, and weak cryptographic protocols also contribute to the wide array of IoT vulnerabilities.

Because IoT devices have become so prevalent in an interconnected world, breaches can impact:

• Consumers: Hacked smart home devices (cameras, thermostats) can provide sensitive information about the users, disrupt domestic activity, and be used as part of a botnet to conduct further attacks across the web.
• Enterprises: Hacked business-critical devices can cause significant damages, including lost time and financial opportunities. Private customer data could be compromised as well. For industrial/OT environments in particular, operational disruption is a critical risk.
• Healthcare: Insecure medical IoT devices put lives directly at risk, as hackers could manipulate insulin pumps to deliver incorrect doses, shut down pacemakers, or hijack ventilators from anywhere in the world. In addition to the physical and clinical risks, personally identifiable information and sensitive health data could be stolen and ransomed.
• Operations: OT security incidents stemming from insecure connected products can lead to equipment damage, production downtime, and threats to human safety.

IoT security has lagged behind device growth. To protect your products and users, build in security early and at every stage.

Begin with these five core best practices:

Public Key Infrastructure (PKI) and other secure forms of device and user authentication will help ensure only authorized users are allowed to access your devices, making breaches less likely.

• Use PKI and digital certificates to securely authenticate devices. SSH certificates in particular help centralize security and implement lifecycle management, which ensures keys are regularly refreshed. We recommend using automated tools to manage your PKI.
• Implement zero-trust architecture to continuously validate devices before they can access network resources. If a device is not validated, it should not have any access to the network. Other devices should only have as much access as needed for their critical tasks.
• Use an IoT PKI strategy tailored to device constraints, provisioning needs, and long-term lifecycle management. Regularly audit this strategy to ensure it’s keeping your devices as secure as possible.
• Implement strong password policies and MFA for IoT device access. Ensure no credentials are kept in plaintext or unencrypted. We recommend using more secure forms of MFA, such as hardware-supported authentication or biometrics.

Hackers should never be able to read the data sent on your network, even if they manage to gain access. Strong data encryption is the best way to protect sensitive information and proprietary data, and your encryption keys should be regularly refreshed.

• Use TLS/SSL encryption for all communications between IoT devices and the cloud. This helps keep data secure and verifies both the server and the client.
• Use hardware-based security features, such as trusted platform modules, for secure data storage. Ensure any backups are also encrypted and kept in a secure location.
• Validate encryption strength across device generations to avoid cryptographic downgrade attacks.

At minimum, any IoT device should require a public key that matches the manufacturer’s private key to securely verify any new code or updates.

• Use secure boot mechanisms to prevent unauthorized firmware from being loaded onto the device.
• Provide regular firmware updates, signed and delivered securely to patch vulnerabilities.
• Use over-the-air (OTA) updates and integrity checks to prevent unauthorized firmware modifications.
• Include firmware security features like rollback protection, version tracking, and cryptographic validation of update packages.

IoT devices form networks among themselves and other cloud systems, meaning one breached device could compromise everything else if network security is not prioritized.

• Segment IoT networks from critical IT systems to minimize attack surfaces.
• Use VPNs and firewalls to prevent unauthorized access to IoT devices.
• Secure APIs with authentication tokens and rate limiting to prevent abuse.
• Isolate connected product interfaces from external traffic whenever possible and use TLS pinning for API calls when possible.

Any security breaches that occur should be stopped as quickly as possible and analyzed to find the source of the incident. The attack vector should then be closed up to prevent further abuse of the vulnerability.

• Deploy IoT security monitoring tools that can detect and respond to anomalies in device behavior. For example, if a smart camera suddenly starts sending massive amounts of data to a new endpoint, an attacker may have gained access.
• Establish logging and auditing workflows to track device activity and detect suspicious patterns.
• Establish real-time telemetry pipelines in OT security environments to detect abnormal behavior or lateral movement attempts.

IoT device security isn’t optional – you must consider and prioritize it at every step of the device lifecycle. Use these steps as the foundation for your broader security program.

To understand where your IoT device security might be lacking, gain a complete understanding of your existing security posture, devices, keys and certificates, etc.

• Conduct an IoT device inventory to identify connected devices. Every device connected to your network should be located and mapped.
• Classify devices based on risk levels. Be able to answer questions like: If an attacker gains access to this device, how much data or how many other devices could they access? How much damage could they do?
• Map device firmware versions and update capabilities to identify risks related to OTA update readiness. Identify ways to provide secure OTA updates to devices where needed to patch other vulnerabilities.
• Evaluate device-level cryptographic agility and whether the connected product infrastructure can support modern IoT PKI practices. Devices should be able to support SSH certificates and other improvements over traditional PKI tools.

Once you know where your security stands, identify where your security should be to properly protect your devices, users, and customers.

• Align security practices to industry standards. Identify relevant guidance and authorities on best practices and develop a plan to implement necessary changes. For example, the banking industry will have different standards than manufacturing.
• Understand the regulatory requirements (GDPR, HIPAA) that apply to your IoT device security. Every layer of your device security strategy needs to align with these requirements.
• Consider following guiding frameworks for connected product security, such as IEC 62443 for automating industrial control systems, the Matter framework for smart home, or ISO15118 for EV charging for example.

After careful planning, begin to implement your IoT device security architecture.

• Design a zero-trust security model for your IoT infrastructure using PKI to securely enforce and verify machine identity. Only trusted and authenticated connections should be allowed.
• Use cloud security solutions to monitor and protect connected devices. Identify and react to threats in real time, preventing intrusion further into your network.
• Use secure provisioning and deprovisioning of IoT devices to prevent unauthorized access. A similar process should be used for your PKI, such as certificates, to keep unauthorized users from accessing secure resources.
• Integrate secure firmware distribution and OTA update infrastructure into your CI/CD pipelines to prevent tampering/streamline deployment. A small insecurity introduced at the very beginning of firmware development could give attackers a large backdoor down the line.

Secure key infrastructure is vital to protecting cloud-connected and IoT devices spread out across the web. A tailored IoT PKI approach helps enforce embedded device protection across fleets.

• Work with PKIaaS providers to build PKI infrastructure that protects your IoT device network.
• Use IoT-specific security platforms to manage the nuances of IoT device security.
• Leverage PKIaaS experience to build crypto-agility into the infrastructure in anticipation of future technology (e.g., quantum).
• Choose a robust PKI solution that supports high-volume certificate issuance, cryptographic policy enforcement, and identity binding across constrained connected products.

IoT security doesn’t stop at the design phase; it requires long-term, automated management of every device identity, certificate, and cryptographic key. With device fleets spanning hundreds of thousands or even millions of connected products, manual certificate lifecycle management does not suffice.

Certificate lifecycle automation platforms like Keyfactor Command for IoT are designed for full visibility and control over machine identities – from provisioning, to commissioning, and through end of life of the device. For connected products, this means that every certificate used to establish device trust, encrypt data, or sign firmware can be issued, renewed, revoked, and replaced automatically without risking service disruption or downtime.

Automation also enables proactive security enforcement across devices and fleets. If a certificate authority is compromised or an algorithm is deprecated, automation powers the rapid response and mass certificate replacement needed for minimal operational impact. This level of cryptographic agility is especially important in IoT environments where physical access is limited or non-existent (smart devices embedded inside of pacemakers, for example).  Automation can also be used when device services are no longer needed, and the OEM or operator desires to decommission and prevent access after a certain point in time.

Ultimately, as machine identities further proliferate, automated certificate lifecycle management provides a scalable way to enforce consistent, policy-driven IoT PKI and machine identity practices across all devices.

The Internet of Things will expand exponentially. This growth will offer hackers more avenues of attack – unless IoT device security takes priority.

New technologies, like quantum computing, are on the horizon. New and creative cryptographic solutions for IoT in the quantum era will be vital. Post-quantum cryptography (PQC) demands a large amount of processing power, which many legacy IoT hardware is unable to support without redesign. It’s also likely that PQC signing of firmware is one of the first applications of post-quantum encryption inside IoT devices, as signing software is a less frequent and lower-volume operation.

Protect your organization from today’s and tomorrow’s threats. Begin by assessing your current connected product security posture and the risks insecure IoT devices pose to your organization’s critical infrastructure. Work with trusted PKIaaS providers to secure your IoT devices now and in the future. Investing in firmware security, OTA resilience, and IoT PKI today lays the foundation for trustworthy connected products at scale