How Zero Trust Enhances Security in Embedded Systems

In today’s digital age, cyber-attacks are becoming increasingly sophisticated and frequent, posing a significant threat to businesses and individuals alike. Traditional security measures are no longer sufficient to protect against these evolving threats, and a new approach is needed. This is where the concept of Zero Trust comes in.

Zero Trust is a security model that assumes no user or device can be trusted by default, regardless of whether they are inside or outside the network perimeter. Instead, it requires all users and devices to be verified and authenticated before being granted access to any resources, applications, or data. In other words, it operates on the principle of “never trust, always verify.”

With the rise of remote work and cloud-based services, traditional network perimeters have become increasingly blurred, making it easier for cybercriminals to infiltrate networks and steal sensitive information. Zero Trust addresses these challenges by placing security controls at every level of the network, providing better visibility and control over who has access to what, and reducing the attack surface for potential threats.

What is Zero Trust?

Zero Trust is a security framework that mandates the authentication, authorization, and continuous validation of all users, both inside and outside an organization’s network, regarding security configurations.

Benefits of Zero Trust

1. Enhanced Security for Remote Connections: Zero Trust provides a secure framework for remote worker connections, ensuring that only authenticated and authorized users can access the network. This is particularly crucial in today’s work-from-home era, where remote access is critical for business continuity. Additionally, Zero Trust can help secure remote edge/embedded devices, which are often the entry points for cyber attackers. By continuously validating security configurations, Zero Trust can prevent unauthorized access and mitigate potential threats.



2. Support for Hybrid Cloud Environments: Zero Trust enables a hybrid cloud environment, allowing organizations to securely access and share data between on-premises and cloud environments. This is particularly important for organizations that use IoT/Connected devices, which need to transmit and receive data from a larger networked organization. By utilizing gateways, Zero Trust can provide secure communication channels and prevent cyber threats from infiltrating the network.
   

   

3. Defense Against Cyber Threats: Zero Trust is a robust security architecture that can help protect against cyber threats such as ransomware and malware attacks. It utilizes embedded devices that can perform operations like secure boot to validate application software. Additionally, mechanisms like Attestation can perform real-time validation and introspection, ensuring that only trusted software and devices are accessing the network. This enterprise-level benefit architecture can prevent cyber attackers from infiltrating the network and causing damage.

The conventional Zero Trust model typically involves hosting services either on-premises or on a remote server that the company has full control over. To connect to these services, a virtual private network (VPN) is often used, which is hosted on a demilitarized zone (DMZ). Users are required to provide their credentials, typically a username and password, to gain access to the VPN.

“This was before the popularity of multi-factor authentication (MFA), where websites and web services were secured through a multifold solution,” says DornerWorks embedded engineer Michael Doran. “The VPN would provide the user with an IP address once the verification process was completed. This would allow the user to enter the company’s internal network where the applications and services are hosted.”

We now know that single-factor authentication is not secure, as most breaches occur due to stolen or weak passwords. Moreover, one of the major security concerns with a VPN is that it can grant users unrestricted access to other internal network assets. For example, if a user logs into an SSH server, they can potentially gain access to other parts of the network. Unless there are additional security measures in place to mitigate or restrict such access, it can pose a significant risk for potential cyber-attacks.

Zero Trust for Developers

From the viewpoint of a developer, supporting the execution, data flow, and updating of an embedded device requires additional development work. This entails verifying each component before it is executed. Ultimately, this translates to a need for more requirements, testing, integration, and validation.

From a manufacturing perspective, the system architect must decide on the best way to provision authentication keys to each device. In addition to the initial keying process, the architect must also consider how to handle the updating of keys and revocation of keys.

Implementing Zero Trust in Secure Systems

At DornerWorks, we use the NIST 800-207 framework as a standard for implementing Zero Trust at both the enterprise level and at the development level.

Our developers follow several key tenets when implementing Zero Trust:

• All data sources and computing services are considered resources.
• All communication is secured regardless of network location.
• Access to individual enterprise resources is granted on a per-session basis. This means that every time a user tries to access a resource, they must go through a secure handshaking/connection process to gain access.
• Access to resources is determined by dynamic policy that considers the observable state of client identity, application/service, and the requesting asset. The policy may also consider other behavioral and environmental attributes.

By adhering to these tenets, DornerWorks engineers can implement a robust Zero Trust security framework that ensures maximum security for our clients.

Zero Trust for Embedded Systems

Embedded systems can be made more secure by implementing a zero-trust architecture. However, there are two critical differences between embedded systems and enterprise environments that need to be considered while devising a security solution.

The first significant difference is that embedded systems have a relatively fixed set of applications, embedded processors, and communication paths. Adding new applications or devices is a rare occurrence, and even upgrading applications or replacing failed devices is infrequent. This stability means that there is less need for frequent updates and changes to the security solution, as the underlying technology infrastructure remains relatively constant.

As Doran explains, “a system integrator can lock-down the system configuration, not just the operating system but also the middleware and applications. Scheduling of trusted applications execution and approved communications paths can be defined statically in a configuration file used at boot time. Integrity testing is still advised to detect if any software component gets altered.“

Embedded systems can benefit greatly from having multiple static configurations available. These pre-approved configurations can be selected at runtime to adapt to different situations, such as a component failure or a change in operational mode. However, as Doran explains, it’s important to note that whenever a configuration change is made, the security functions need to continuously maintain a secure state before, during, and after the change is implemented.

Designing and Building a Zero Trust System

Designing and building a Zero Trust system is a complex process that requires careful planning, a deep understanding of security principles, and the ability to identify and mitigate potential risks. Here are some key considerations and steps involved in the design and development process:

• Identify the assets: The first step is to identify the assets that need to be protected. This includes data, applications, and devices. Once you know what you are trying to protect, you can design a system that will meet those requirements.
• Assess the risks: Next, you need to assess the risks that are associated with the assets you are trying to protect. This includes identifying potential threats, vulnerabilities, and attack vectors. This information will help you design a system that can mitigate those risks.
• Design the architecture: With a clear understanding of the assets and risks, you can begin to design the architecture of the system. This includes defining the boundaries of the system, the access control policies, and the communication protocols.
• Implement access controls: Access controls are a critical component of a Zero Trust system. These controls define who can access what resources and under what conditions. This includes authentication, authorization, and identity management.
• Implement monitoring and logging: Monitoring and logging are essential components of a Zero Trust system. These components allow you to detect and respond to security incidents in real-time. This includes log aggregation, threat detection, and incident response.
• Test and evaluate: Once the system is built, it needs to be thoroughly tested and evaluated to ensure that it meets the security requirements. This includes vulnerability testing, penetration testing, and code review.

Some key considerations to keep in mind when designing and building a Zero Trust system include:

• Least privilege: Only grant the minimum level of access necessary for each user or application to perform their tasks.
• Micro-segmentation: Divide the network into smaller segments, each with its own access controls and security policies.
• Data protection: Implement strong encryption, data integrity checks, and access controls to protect sensitive data.
• Threat intelligence: Use threat intelligence to proactively identify and respond to security threats.
• Regular updates and maintenance: Regularly update and maintain the system to ensure that it remains secure against the latest threats.

Designing and building a Zero Trust system is not a one-time event but an ongoing process. The system needs to be regularly evaluated, updated, and maintained to ensure that it remains secure against the latest threats. By following these key considerations and steps, you can design a system that is resilient, secure, and able to protect against even the most advanced security threats.

Protecting Against Different Types of Attacks

A Zero Trust approach can protect against a range of different attacks by providing multiple layers of security that must be successfully navigated to gain access to a system. Zero Trust can help you prevent your data from being compromised by limiting attack surfaces through isolation. This way, any data sent or received by the device is encrypted. Zero Trust can also help you prevent lateral movement in your system using a robust policy engine and introspection of any unauthorized entry.

Zero Trust can also help you prevent data loss through:

• Policies regarding disposal of “stale” data
• Business logic is valuable
• PKI (public/private) information is valuable
• Current transaction information
• Device configuration
• Logs

Here are some other types of attacks that Zero Trust security can protect against:

Phishing attacks: Phishing attacks rely on tricking users into providing sensitive information. Zero Trust security can help prevent these attacks by ensuring that users only have access to the data they need to do their jobs and by using multi-factor authentication to verify their identities.

Malware attacks: Malware attacks can be devastating for embedded systems, often causing permanent damage to the system. A Zero Trust approach can help mitigate these attacks by requiring continuous monitoring of system activity and verifying the integrity of software before it is executed.

Denial-of-service attacks: Denial-of-service attacks can cause system downtime, preventing users from accessing important data. A Zero Trust approach can protect against these attacks by using load balancers to distribute traffic and by limiting the amount of traffic that can be directed to a single server.

Insider threats: Insider threats can be difficult to detect, as these individuals already have access to the system. A Zero Trust approach can help mitigate these threats by monitoring user activity and implementing strict access controls that limit the amount of data users can access.

Advanced persistent threats: Advanced persistent threats (APTs) are long-term attacks that are designed to remain undetected. Zero Trust security can help prevent these attacks by implementing continuous monitoring and analysis of system activity, detecting anomalies, and responding to potential threats in real-time.

Zero-day attacks: Zero-day attacks are attacks that exploit previously unknown vulnerabilities in software. Zero Trust security can protect against these attacks by continuously monitoring system activity and detecting any suspicious behavior.

Ransomware attacks: Ransomware attacks can cause significant damage to embedded systems by encrypting critical data and demanding a ransom in exchange for its release. A Zero Trust approach can help mitigate these attacks by implementing regular data backups and using strong encryption to protect data.

Supply chain attacks: Supply chain attacks are attacks that target the software supply chain, often by inserting malicious code into legitimate software. A Zero Trust approach can help protect against these attacks by implementing strict security controls at each stage of the supply chain.

Overall, a Zero Trust approach can provide a comprehensive security solution for embedded systems, protecting against a wide range of different types of attacks. By implementing continuous monitoring, access controls, and other security measures, Zero Trust security can help ensure that embedded systems remain secure and protected at all times.

Differences from Traditional Security Models

Zero Trust is a departure from traditional security models that assume everything inside a network can be trusted, while outsiders should be kept at bay. The Zero Trust model, on the other hand, doesn’t assume anything is safe, and instead requires strict identity verification for all users and devices trying to access resources.

Here are some of the key differences between the Zero Trust model and traditional security models:

• Traditional security models are perimeter-based, while Zero Trust is identity-based.
• Traditional models allow for broad access to resources, while Zero Trust limits access to only what is necessary for the user or device to perform its intended function.
• Traditional models rely heavily on firewalls and other perimeter-based controls, while Zero Trust relies more on encryption, multi-factor authentication, and other identity-based controls.
• Traditional models are reactive, waiting for an attack to happen before responding, while Zero Trust is proactive, assuming attacks will happen and continuously monitoring for them.
• Traditional models are more static, with controls that are typically configured once and left in place, while Zero Trust requires a more dynamic approach that can adapt to changing environments and threats.

Here are some advantages of the Zero Trust approach:

• Improved security posture: Zero Trust provides greater protection against data breaches and other types of attacks.
• Greater visibility: By requiring strict identity verification for all users and devices, Zero Trust allows for greater visibility into what’s happening on the network.
• More granular control: Zero Trust limits access to only what is necessary, which means that even if a device or user is compromised, the damage they can do is limited.
• Better compliance: Many industries and regulatory bodies require strict access controls and monitoring, and Zero Trust can help organizations meet these requirements.

However, there are also some potential disadvantages to the Zero Trust approach:

• Complexity: Implementing a Zero Trust model can be complex, requiring a significant investment of time and resources.
• User experience: Strict identity verification and other controls can make it more difficult for users to access the resources they need, potentially leading to frustration and decreased productivity.
• Cost: Implementing a Zero Trust model may require significant investment in new technologies and personnel to manage them.

Overall, the benefits of the Zero Trust approach generally outweigh the potential disadvantages, particularly in today’s security landscape where the threat of attacks is constantly increasing.

User Experience and Zero Trust

Zero Trust security is a crucial aspect of modern security practices, but it’s important to consider the user experience when designing and implementing these systems. The following strategies can help minimize user impact while ensuring maximum security:

• Role-based access control: Users should only have access to the resources they need to perform their job functions. Implementing role-based access control helps ensure that users are not burdened with unnecessary permissions or restrictions.
• Continuous authentication: Rather than relying on a single authentication event (e.g., a login), continuous authentication monitors user behavior and ensures that the user remains authorized to access the system. This helps reduce the need for frequent logins and can help prevent unauthorized access.
• Simplify user interfaces: Complex user interfaces can be overwhelming and may increase the risk of user error. Simplifying the interface and reducing the number of decisions users need to make can help reduce the likelihood of mistakes.
• Provide clear guidance: Users should be provided with clear instructions and guidance for using the system securely. This can include training on how to avoid common security pitfalls and guidance on how to report security incidents.
• Use automated processes: Automated processes can help reduce the burden on users while ensuring that security protocols are followed. For example, automated password reset processes can help reduce the need for users to contact IT support.

Overall, it’s important to find a balance between security and user experience. By considering user needs and implementing strategies to minimize user impact, organizations can ensure that Zero Trust systems are effective without impeding productivity.

Examples of Successful Zero Trust Implementations

Examples of successful Zero Trust implementations abound. Notable instances include:

• Google: Google implemented a Zero Trust model, which they call BeyondCorp, to secure their internal network. The model ensures that every device accessing the network is authenticated and authorized, regardless of whether it’s inside or outside the corporate network. Google’s implementation of Zero Trust has enabled them to secure their data and applications against attacks like phishing and malware.
• Capital One: In 2019, Capital One was hit by a data breach that compromised the personal information of over 100 million customers. The hacker was able to exploit a vulnerability in the company’s firewall to gain access to their systems. Following the breach, Capital One implemented a Zero Trust approach to security, which has enabled them to identify and isolate suspicious activity in real-time, thereby preventing potential attacks.
• Microsoft: Microsoft has implemented a Zero Trust security model to protect their Azure cloud infrastructure. The model ensures that every access request to the cloud is verified, regardless of where the request is coming from. This has enabled Microsoft to secure their cloud infrastructure against threats like DDoS attacks and unauthorized access.

In all these examples, the Zero Trust approach made a significant difference in protecting against attacks and ensuring the security of sensitive data and applications. The approach ensured that every access request was verified and authorized, thereby preventing unauthorized access and minimizing the risk of attacks.

Adapting to Evolving Security Threats

Adapting to evolving security threats is a critical aspect of the Zero Trust approach. As attackers come up with new techniques and tools, organizations must be able to respond accordingly to keep their systems secure. DornerWorks maintains a proactive approach to security, keeping up with the latest threats and making changes to their Zero Trust approach as necessary. Here are some strategies that DornerWorks employs to adapt to evolving security threats:

• Continuous Monitoring: DornerWorks continuously monitors their systems for potential security breaches. This allows them to identify any suspicious activity as soon as it occurs, enabling them to respond quickly and effectively.
• Regular Updates: DornerWorks regularly updates their security policies and procedures to address emerging threats. They also update their software and firmware to incorporate the latest security patches and upgrades.
• Collaboration: DornerWorks works closely with their clients and partners to stay up-to-date on the latest security threats and to develop effective responses. This collaboration allows them to share best practices and to leverage the expertise of others in the industry.
• Risk Assessments: DornerWorks conducts regular risk assessments to identify potential vulnerabilities and to develop strategies for mitigating those risks. They also perform penetration testing and other security assessments to test the effectiveness of their security measures.
• Training: DornerWorks provides ongoing training to their employees to ensure that they are aware of the latest security threats and best practices. This training includes everything from basic security awareness to advanced technical training on specific security technologies and techniques.
• Threat Intelligence: DornerWorks stays up-to-date on the latest threat intelligence by subscribing to threat feeds and monitoring security forums and other online sources of information. This allows them to quickly identify emerging threats and to develop effective responses.

The Zero Trust approach is not a one-time implementation but a continuous process that requires ongoing attention and adaptation to evolving security threats. DornerWorks employs a variety of strategies to stay up-to-date on emerging threats and to adapt their Zero Trust approach accordingly. By doing so, they can provide their clients with the highest level of security for their embedded systems.

Conclusion

Zero Trust is a paradigm shift in security that is becoming increasingly critical in embedded systems. With traditional security models failing to keep pace with evolving threats, Zero Trust takes a proactive approach that trusts no one and nothing, constantly verifying and validating users, devices, and applications before granting access to any resources. By following a Zero Trust approach, businesses can better protect themselves from a wide range of cyberattacks, including those that are often undetectable by traditional security models.

DornerWorks has been at the forefront of Zero Trust security. Our engineers work closely with their clients to design and build Zero Trust systems that meet their specific needs, while also ensuring that user experience is not impacted.

To adopt Zero Trust security in their embedded systems, it helps to work with a trusted partner like DornerWorks. By scheduling a meeting with our team, you can learn how to turn ideas into reality and develop secure, resilient, and scalable embedded systems that will help protect against cyber threats. Schedule a meeting with our team so you can enjoy peace of mind, knowing that your business and customers are protected.