How PKI secures IoT Ecosystem?

The rapid adoption of IoT devices and their advancement over the past decades has transformed daily life, offering unparalleled convenience and connectivity. However, this growing reliance on IoT has also brought about an increase in security breaches, highlighting the urgent need for better protective measures. Sensitive data, cloud technologies, and a huge number of electronic smart devices are connected through the internet, providing a cybercriminal with a large area to attack. Hence, it became an urgent necessity to safeguard these IoT devices as they play a vital role in one’s life. 

Introduction

Public Key Infrastructure (PKI) for the Internet of Things (IoT) is a way to provide security in IoT environments. It uses digital certificates and cryptographic keys to ensure secure communication among IoT devices. PKI manages authenticity, confidentiality, and data integrity among the devices in an IoT ecosystem. 

Here is a brief of how PKI is involved in security concerns of the IoT ecosystem: 

Authentication 

Authentication in the IoT ecosystem is all about Access Control. If an IoT device gains access to your network, there is a huge possibility that the user of that device also has access to all the data you are sharing on that network. Hence, it is necessary to secure the authentication process in the IoT ecosystem so that only the right devices can have access to the right resource or data on the network. 

Encryption 

IoT devices carry a lot of sensitive information that requires encryption processes to ensure data confidentiality. Various threats could occur when implementing a poor encryption process. Some of them can be data breaches, Man-In-The-Middle (MITM) attacks, data tempering, etc. 

Data Integrity 

Data integrity plays a vital role in an IoT environment. It ensures that the data created, transmitted, and saved by IoT devices is true, uniform, and unchanged during its lifecycle. If left unchecked, this non-compliance can lead to massive system failures, data loss, financial losses, and, more importantly, incorrect decision-making.  

Secure Communication (EST)

Enrollment over Secure Transport (EST) is a key enabler of secure communication in the IoT ecosystem, automating the provisioning, renewal, and management of PKI certificates. EST is described in RFC 7030, and it facilitates automated certificate issuance, renewal, and management by securely exchanging information between clients and Certificate Authorities (CAs) via TLS, eliminating the need for shared secrets or passwords used in older protocols like Simple Certificate Enrollment Protocol (SCEP). 

Why are IoT devices more Vulnerable than Traditional Electronic Devices? 

IoT Devices are more vulnerable than traditional electronic devices for the following reasons. 

Lack of Security 

Some IoT devices lack security issues to maintain low costs in the market. Sometimes, security standards are compromised to maintain the affordability of the product or device. 

In 2024, a study revealed that certain TP-Link Tapo devices, such as smart bulbs and plugs, contained vulnerabilities that allowed attackers to extract sensitive information, including user credentials and Wi-Fi network details. These weaknesses could enable unauthorized access to users’ networks and devices.

High Interconnectivity and Access points 

IoT devices are generally designed to communicate with each other, resulting in a highly interconnected environment. A breach in one device may lead a hacker to exploit the entire network, as IoT devices trust each other in a network by default. 

A vulnerability in Kia’s web portal allowed attackers to reassign control of Kia vehicle’s internet-connected features from the owner’s smartphone to their own devices. It gave them the ability to track the vehicle, unlock the vehicle’s doors, honk the horn, or even start the vehicle’s ignition system, showing the dangers of interconnectivity in IoT systems in modern vehicles. 

Use of Default or Weak credentials 

Users either do not change the default usernames and passwords of IoT devices or use weak passwords instead. Attackers can access devices without hacking techniques because these default credentials are easy to guess. 

In September 2024, The Raptor Train botnet compromised over 200,000 devices, including routers and IP cameras, by exploiting default or weak passwords. This large-scale attack underscores the risks associated with not updating factory-set credentials. 

Physical Accessibility and Tempering 

Most IoT devices are mounted in public or remote areas, making them very vulnerable to being accessed for tampering by attackers. A physical attack may make the attackers able to alter, change, or even add the malevolent codes into the gadget at hand, thus leaving the integrity exposed and leaving other integrated systems on the risk verge. 

For instance, there are real-life attacks regarding physical tempering, like the Smart Lock Fingerprint attack in 2022, where researchers showed that some smart lock devices could get your fingerprint without your knowledge. In particular, the “Droplock” attack required the physical tempering of the devices to collect biometric data, undermining security. 

Delayed Security updates 

Most of the present IoT devices tend to receive relatively fewer software updates than more conventional electronic devices, such as laptops and phones, which are often updated with new security patches by the manufacturers. 

In August 2024, a well-known vulnerability was found in AVTECH IP cameras, a flaw initially discovered in 2018 and actively exploited to spread the Mirai malware, which targets IoT devices to form botnets for large-scale Distributed Denial of Service (DDoS) attacks. The lack of timely security updates on these devices allowed the attack to persist for years, resulting in compromised devices being used to orchestrate DDoS attacks that overwhelmed targeted servers, causing significant service outages, financial losses for businesses, and disruptions to consumers relying on affected services. 

What are the Key Security Requirements for IoT? 

Some of the security requirements for IoT devices to maintain confidentiality, integrity, and availability of the data are: 

Authentication 

It is one of the mechanisms of security that only allows bodies to have access to or be able to read the sent or stored data. IoT devices use various authentication mechanisms, such as fingerprint, face, or Retina scans, collectively known as biometrics or digital certificates, to verify users and devices. 

Various IoT devices in today’s world maintain the standards of high-end authentication and keep the devices secure from unauthenticated users. Some examples are the Amazon Echo Show, enabled with 2-factor authentication (2FA), and the Apple HomePod Mini, which requires an Apple ID to log in with 2FA. Tesla IoT features that require fingerprint or facial recognition through the Tesla app to access connected devices and many more. 

Authorization

It is necessary to maintain control permissions and access levels to ensure that each device can perform authorized actions only. Access control can be obtained by using Role-Based access control (RBAC) mechanisms. 

Various organizations have high-end authorization mechanisms for their products. Some of them are: 

Cisco Meraki MX Security Appliances: According to Cisco Meraki Docs, it comes with an RBAC mechanism where the Administrator can assign different roles (e.g., viewer, editor, admin) to users, limiting what each user can access or modify. 

Microsoft Azure Sphere IoT Security Platform: As per Microsoft Azure, Azure Sphere uses PKI to authenticate and authorize devices within the PKI ecosystem. Each Azure Sphere device is provisioned with a unique, unforgeable cryptographic key at the time of manufacturing, which is used to create a device certificate. This certificate is chained to a catalog-level certificate and ultimately to a Microsoft certificate, establishing a chain of trust. The Azure Sphere Security Service employs these certificates to verify device identities and ensure that only authenticated devices can access the network, thereby maintaining the integrity and security of the IoT ecosystem. 

Data Integrity 

It guarantees that the data has not been interfered with or modified while in transit or at rest. To ensure the authenticity and integrity of data, techniques such as hashing (SHA-256, SHA-3) and digital signatures are applied. 

Hashing generates a unique fixed-length hash value for a given input, which changes entirely if the original data is altered, making it a reliable method for verifying data integrity during transmission or storage. Digital signatures further enhance security by combining hashing and encryption; the sender creates a signature by encrypting the hash of the data with their private key, and the receiver decrypts it with the sender’s public key to verify both the data’s integrity and the sender’s authenticity. 

Here are a few organizations that employ different methods to protect data integrity on their IoT devices: 

AWS IoT Core: According to Amazon AWS Docs, AWS uses the SHA-256 algorithm to generate message digests for data transmission. ECDSA (Elliptic Curve Digital Signature Algorithm) provides compact and efficient signing for IoT devices. 

Various other organizations are using SHA-2 family hashing algorithms to generate message digests and different digital signature algorithms like RSA-2048, DSA, ECDSA, etc. Google Cloud IoT Core, CISCO IoT Threat defense, and Samsung SmartThings Platform are some real-life examples where high-quality data integrity is maintained. 

Secure Communication protocols 

IoT devices should use secure protocols for transmitting and storing data. As IoT devices often operate in interconnected environments, they are vulnerable to a wide range of cyber threats, including data interception, unauthorized access, and tampering. Employing secure communication protocols such as HTTPS (Hypertext Transfer Protocol Secure), TLS/SSL (Transport Layer Security/Secure Sockets Layer), and DTLS (Datagram Transport Layer Security) helps protect data in transit by encrypting it, thus preventing attackers from reading or modifying the information exchanged between devices and servers. 

Let’s explore a few industry-leading projects in the IoT space and their strategies for implementing strong security measures to ensure secure communication among devices and agents. 

Smart Singapore: Initiatives for Singapore to use IoT devices at the Urban Level. It also includes smart lighting, waste management, and surveillance systems. By implementing HTTPS and SSL/TLS protocols, Singapore preserves the privacy and integrity of information associated with traffic management, public safety, and environmental monitoring while securely transmitting data collected across multiple sensors. 

Industrial IoT Deployment by Siemens: Siemens has integrated IoT devices within its manufacturing processes to monitor equipment performance and optimize operations. Using DTLS (Datagram Transport Layer Security) and TLS/SSL, Siemens ensures that data exchanged between machinery and central control systems is encrypted, preventing unauthorized access and potential industrial espionage. 

Secure Boot and Firmware Updates

IoT devices must ensure they boot securely and are protected from physical tempering and loading malicious firmware. This is because a secure boot can check for malicious firmware before the device starts up. Regular updates via cryptographically signed packages can keep devices secure for a long time. 

Some of the real-life examples that are implemented by various organizations are: 

Secure Boot Mechanism for IoT Firmware Updates: A leading organization in digital security solutions has developed a secure boot mechanism designed to protect IoT devices from malicious firmware tampering. 

They implemented public-key cryptography to manage secure keys, ensuring only authorized entities can access and update firmware. Firmware updates are digitally signed using secure keys, verifying their authenticity and integrity. They also ensure that only valid firmware is executed, preventing malicious code from running on the device. 

By implementing this secure boot mechanism, the organization enhances the security of IoT devices, ensuring that firmware updates are genuine and have not been tampered with, thereby reducing the risk of malware attacks. 

Microsoft’s Azure Sphere for IoT Device Security: Azure Sphere is a comprehensive IoT security solution developed by Microsoft, consisting of a secured microcontroller unit (MCU), a custom Linux-based operating system, and a cloud-based security service. 

Azure Sphere MCUs implement a hardware-based root of trust, ensuring that devices boot securely and only run genuine, untampered firmware. It provides automatic, secure updates to the operating system and applications, ensuring devices remain protected against emerging threats. 

By providing an end-to-end security solution with secure boot and automated firmware updates, Azure Sphere helps protect IoT devices from physical tampering and malicious software, ensuring long-term device security. 

What are the advantages of Introducing a PKI to IoT Devices? 

Introducing PKI into the IoT ecosystem offers numerous advantages for secure device communication. Here are some practical applications for the PKI in IoT. 

Strong Authentication 

Case Study: Global Manufacturer’s Journey to Automating PKI 

Overview: A prominent international devices producer struggled to manage PKI security in the breadth and depth of its complex network of IoT devices. The manual processes were time-consuming and prone to errors, leading to potential security vulnerabilities. 

Implementation: The manufacturer collaborated with a leading PKI services provider and automated PKI processes, so every IoT device was provisioned with a unique digital certificate, enabling them to authenticate properly. This reduced the risk of unauthorized device access and streamlined certificate issuance and management. 

Outcome: The automated PKI solution improved the security of the manufacturer’s IoT ecosystem by minimizing the device threats associated with devices communicating within the network based on authentication. These would include maximized operational efficiency with minimal risk of human error when managing certificates. 

Data Confidentiality through Encryption 

Example: Securing IoT Devices with PKI 

Overview: IoT devices commonly send sensitive data over networks, so the use of encryption is critical to protect against eavesdropping and data breaches. 

Implementation: Organizations can implement PKI technology as a solution by setting up asymmetric key pairs to encrypt IoT device data ocean. Here, each device is assigned a pair of private and public keys, which are used for the encryption and decryption of data. 

Outcome: Hence, even if the data transmission is intercepted, the transmitted information is not readable to any person who does not have the key. The strong encryption mechanisms of PKI help to ensure data privacy in IoT communications. 

Data Integrity with Digital Signatures 

Example: Ensuring Data Integrity in IoT Communications 

Overview: Ensuring data integrity is critical in IoT ecosystems to prevent malicious interference with commands and data. 

Implementation: PKI supports the use of digital signatures, which authenticate and ensure the integrity of data being exchanged. For example, when an IoT device sends data, it signs the data with its private key. The receiving party can then use the public of the device to verify that the data has not been modified. 

Outcome: Digital signatures provide assurance that the data received is exactly as sent, preventing unauthorized modifications and ensuring trust in IoT communications.  

Support for Secure Device Updates

Example: Secure Firmware Updates in IoT Devices 

Overview: Regular firmware updates are very important for IoT devices as they allow devices to fix vulnerabilities and add and improve features. Unsecured update mechanisms, however, can be used to install malicious software. 

Implementation: Use PKI to allow the device to accept only digitally signed firmware updates that come from authorized sources. During installation, the device checks the digital signature applied by the firm using the public key that was obtained from a trusted source. 

Outcome: This process prevents unauthorized or malicious firmware from being installed, maintains the device’s security, and protects against potential cyber-attacks.  

Compliance with Regulatory Standards

Example: PKI in Healthcare IoT Devices 

Overview: Healthcare organizations are subject to numerous regulatory guidelines, such as HIPAA, enforcing the protection of patient data. 

Implementation: With PKI-integrated IoT medical devices, healthcare providers will be able to deliver strong encryption, data integrity, and authentication. Digital certificates authenticate device identities and protect patient data in transit, which are both aligned with regulatory compliance. 

Outcome: Implementing PKI helps healthcare organizations meet compliance standards, protect sensitive patient information, and establish trust in their IoT medical devices. 

Why choose Managed PKI over in-house PKI? 

In today’s fast-paced digital world, businesses need secure and efficient solutions to manage device identities and safeguard sensitive data. Managed PKI offers a streamlined and scalable alternative to the time-consuming and resource-intensive process of setting up an in-house PKI. Below are the key advantages that make Managed PKI the smarter choice for organizations. 

Speed and Growth Flexibility

Managed PKI is like having a pre-built security system ready to go. Instead of building everything from scratch, which takes time and money, you can start using it right away. Plus, it’s super flexible like renting an office that grows or shrinks with your business needs. You can easily scale up security or trim it down based on your goals. 

Special Hardware Security Management

Managed PKI includes fancy hardware called HSMs (Hardware Security Modules) that act like high-tech safes for your secret keys and codes. The best part? You don’t need to spend a ton buying these yourself. With a managed PKI, you get all the benefits of secure hardware without the huge upfront costs. 

Certificate Management 

Every device in your system needs a digital ID, like a badge, to prove it belongs. Managed PKI takes care of creating, updating, and even canceling these IDs when needed, just like an automated HR system for security badges. It also keeps a list of “bad badges” so no one can sneak in. 

Secure Facilities and Insider Threat Protection 

The managed PKI providers have super-secure buildings, like fortresses, to protect their systems. They use security measures such as fingerprint scanners, cameras, and even guards to keep everything safe. They also have strict rules to prevent insider threats, like requiring multiple people to approve sensitive actions and running background checks on employees. 

Advanced Device Identities

Managed PKI can provide extra-smart digital IDs for devices. Imagine a super badge that not only proves who you are but also tells what you’re allowed to do and can check if your software is safe. These advanced IDs are perfect for IoT devices that need more than basic security. 

Flexible Provisioning Options

Managed PKI lets you set up device security in two ways:

• Factory Provisioning: This is like giving devices their IDs during manufacturing and securely storing the info right inside them.
• Cloud-Based Provisioning: Think of this as giving devices a temporary ID (a “starter badge”) at the factory. Later, once the device is in use, it gets its full secure ID remotely through the cloud. This makes managing devices across different locations much easier.

Certificate Authority Oversight

Managed PKIs follow strict rules set by organizations like WebTrust to ensure they’re doing everything right. It’s like having a third-party inspector who makes sure your security is top-notch and follows all the best practices. 

How can you manage PKIs for IoT? 

Managing Public Key Infrastructure (PKI) for Internet of Things (IoT) devices is essential to ensure secure communication, authentication, and data integrity within the IoT ecosystem.

Automated Certificate Lifecycle Management 

Issuing, distributing, revoking, and renewing a certificate through an automated system helps to reduce human errors and increase security. By automating this process, fresh and unexpired certificates or TLS connections with customers will be used while minimizing the chances of expired certificates. 

However, real-world scenarios reveal various challenges. One common issue is incorrect configuration, where automation pipelines may be set up improperly, leading to failed renewals or distribution of invalid certificates. Similarly, renewal failures can occur due to network issues, misconfigured permissions, or external dependencies, such as relying on third-party services. 

Automating the removal of compromised certificates is often ignored, which can delay updates and leave systems at risk. Older systems add to the challenge because they may not work with modern protocols or encryption standards, causing trust issues with new certificates. Relying too much on automation without proper monitoring and alerts can make organizations unaware of certificate problems, like failures or expirations, until they cause disruptions. 

Encryption Consulting’s CertSecure Manager 

Encryption Consulting offers a certificate lifecycle management solution that automates the entire certificate lifecycle process, ensuring IoT devices maintain valid and secure certificates without manual intervention.  

Onboarding Secure Devices 

Secure device onboarding involves provisioning devices with unique cryptographic identities before they connect to the network. This process ensures that only authenticated devices can access the IoT ecosystem. 

However, in real-world scenarios, scalability is a challenge in secure onboarding of devices. In large-scale IoT networks, onboarding hundreds or thousands of devices can be resource-intensive and prone to errors. For example, a failure in the provisioning process due to misconfigured credentials or network interruptions can leave devices unauthenticated, resulting in delays or gaps in security. 

Compromised devices also pose a threat during onboarding. Attackers can inject malicious devices into the network that appear legitimate but are designed to exploit vulnerabilities. For example, during the Mirai botnet attack, insecure IoT devices were onboarded into networks and subsequently used for DDoS attacks. 

Microsoft Azure IoT Device Provisioning Service (DPS)  

Microsoft Azure IoT Device Provisioning Service (DPS) simplifies and secures the onboarding of IoT devices to Azure IoT Hub. It enables zero-touch provisioning, allowing devices to automatically register and configure themselves without manual intervention. Supporting multiple authentication methods like TPM, X.509 certificates, and symmetric keys, DPS ensures strong security. 

Define Access Control Policy 

Role-Based Access Control (RBAC) primarily restricts the access of the users/devices as per their defined roles, which significantly decreases the risk of unauthorized access and avoids breaches. 

However, in real-world scenarios, implementing and maintaining these policies can be challenging. One common issue is role misconfiguration, where users or devices are assigned excessive privileges due to poorly defined roles or incorrect implementation. This can lead to unauthorized actions or data breaches if attackers exploit over-permissioned accounts. 

RBAC can also struggle in large-scale systems with complex hierarchies. Organizations with many roles and permissions often face difficulty ensuring that all assignments align with the principle of least privilege. 

Encryption Consulting PKI Management Solutions 

Encryption Consulting provides PKI management tools that support RBAC, allowing organizations to define and enforce access policies across their IoT devices.  

Use a Hierarchical PKI Structure 

A hierarchical PKI structure consisting of root Certificate Authority (CA) and intermediate CAs provides a scalable and flexible mechanism for managing certificates throughout large IoT networks. 

In real-world scenarios, managing a hierarchical PKI structure in large IoT networks presents several challenges. While a root Certificate Authority (CA) and intermediate CAs provide scalability and flexibility, maintaining the integrity and security of this structure is complex. One key issue is ensuring the secure storage and operation of the root CA, as it serves as the trust anchor for the entire PKI system. If the root CA is compromised, it can risk the trustworthiness of all certificates in the network. 

Scalability is another concern, particularly in dynamic IoT environments where devices are continuously added or removed. Ensuring that new devices are issued certificates quickly and revoked certificates are effectively propagated across the network can be difficult. A delay in these processes may lead to unauthorized access or operational disruptions. 

Encryption Consulting PKI Management Solutions 

Encryption Consulting offers a scalable PKI solution with a hierarchical structure, enabling secure and efficient certificate management for millions of IoT devices. By leveraging root and intermediate CAs, the solution streamlines certificate issuance, renewal, and revocation. With advanced automation and centralized management, it simplifies operations while ensuring high end security and compliance across large IoT networks.   

Regular Key Rotation and Renewal 

Rotate cryptographic keys and renew certificates to mitigate the risk of key compromise and improve overall security. To ensure uniformity and reduce manual errors, we can automate the process of key rotation and renewal. 

In real-world scenarios, regular key rotation and certificate renewal are critical for maintaining strong security. Manual key rotation is particularly error-prone, and organizations may skip or delay updates, leaving sensitive systems vulnerable. For example, in an IoT ecosystem, if one device’s certificate is not renewed on time, it could lead to connection failures or, worse, allow unauthorized access through an expired key. 

Automating key rotation and certificate renewal can significantly reduce the chances of human error and ensure that security protocols remain up to date. In practice, the lack of automation or poor implementation can lead to downtime, security breaches, or the misuse of compromised keys. Regular auditing and the use of automated tools to handle these processes are essential for maintaining the integrity of cryptographic systems and minimizing the risk of key compromise. 

Automated Key Management 

Some organizations offer automated key rotation and renewal services, ensuring that IoT devices maintain up-to-date cryptographic keys without manual intervention. Automated Key Management solutions help organizations enforce policies for regular key rotation and certificate renewal, thereby eliminating the human error associated with manual processes. These systems track key lifecycles, schedule rotations, and automatically update devices with new keys, ensuring a seamless and secure environment. This is critical for IoT devices, which are often deployed at scale and may require periodic updates for security compliance.

Secure Storage of Private Keys 

Storing private keys in Hardware Security Modules (HSMs) or encrypted software vaults protects them from unauthorized access and potential breaches. In real-world scenarios, securing private keys is critical because they are the foundation of cryptographic security.  

Private keys, if compromised, can lead to data breaches, unauthorized access, or even total system compromise. One of the primary challenges organizations faces is ensuring that private keys are stored in a way that protects them from theft or exposure, especially in large-scale environments where they are spread across multiple systems. 

A common problem is the improper storage of private keys in plaintext or on easily accessible locations such as databases or file systems. Storing keys in these locations without proper encryption or access controls significantly increases the risk of compromise, especially if an attacker gains access to the system. For example, during a cyberattack, attackers may target unsecured key storage locations to gain access to sensitive data or to impersonate users or devices. 

Encryption Consulting’s HSM-as-a-Service 

Encryption Consulting provides customizable, secure, and high-assurance Hardware Security Module (HSM) solutions that offer high scalability and quick deployment. These HSMs ensure advanced data protection by securely managing cryptographic keys, certificates, and sensitive information. They provide strong protection against unauthorized access and tampering, ensuring compliance with industry standards. With their scalability and easy integration, Encryption Consulting’s HSM solutions are ideal for businesses seeking to enhance security while minimizing deployment time and complexity. 

By adopting these best practices and leveraging advanced PKI management solutions, organizations can enhance the security and integrity of their IoT ecosystems, ensuring strong authentication, data confidentiality, and compliance with regulatory standards. 

How can Encryption Consulting help? 

With Encryption Consulting’s PKIaaS, organizations can redirect their focus to core business objectives and product development, knowing that a secure, efficient, and compliant PKI system safeguards their IoT infrastructure. We provide expert support and insights to help our clients adapt to evolving security needs, allowing them to grow with confidence and peace of mind.  

Additionally, Encryption Consulting’s HSM-as-a-Service and CertSecure Manager provide powerful solutions for implementing PKI in IoT ecosystems by ensuring secure key management, automating certificate lifecycle processes, and enforcing granular access controls. HSM-as-a-Service protects cryptographic keys and facilitates secure communication, while CertSecure Manager streamlines digital certificate management with automation and RBAC features to mitigate risks and enhance scalability. Together, these tools empower organizations to establish a secure, compliant, and efficient PKI framework tailored to the dynamic needs of IoT environments. 

Conclusion 

To draw a conclusion, as IoT devices are becoming more and more popular day by day, their integration into interconnected ecosystems brings unparalleled convenience and efficiency. This rapid adoption also introduces significant security challenges, including vulnerabilities to cyber-attacks, unauthorized access, and malware threats. PKI serves as a foundation for IoT security by offering strong mechanisms for ensuring data integrity, authentication, and encryption. By using PKI, organizations can create a trusted environment for device communication that helps in protecting sensitive information and increases user trust. 

In the latest IoT ecosystem, implementing a scalable and efficient PKI system is crucial for securing devices that ensure the safe and uninterrupted functionality of these devices. Adopting PKI addresses current security concerns and prepares for future advancements in IoT technology, ensuring more innovation and fewer emerging cyber threats.