Securing Non-Human Identities with Hardware-Attested Identity

Introduction: The Expanding Universe of Non-Human Identities

Imagine a world where every machine, workload, and api has its own unique, verifiable identity. This is the reality we're moving towards, but it comes with its own set of challenges. Let's dive into the expanding universe of Non-Human Identities (NHIs) and why securing them is paramount.

Non-Human Identities (NHIs) encompass machines, workloads, services, and apis. Think of automated systems in healthcare managing patient data, retail systems processing transactions, or financial apis handling payments.

The growth of NHIs is exponential. (The Impact of the Exponential Growth of Non-Human Identities ...) As organizations embrace cloud-native architectures and microservices, the number of NHIs dwarfs human users. (Securing cloud architectures in the age of non‑human ...) This proliferation introduces significant security risks. Unmanaged or poorly secured NHIs can lead to lateral movement within a network, data breaches, and privilege escalation.

Traditional Identity and Access Management (IAM) solutions are often user-centric. They lack the granularity and automation needed to manage NHIs effectively. Managing NHI credentials – secrets, keys, and certificates – at scale becomes a complex, error-prone task.

Hardware-attested identity offers a robust solution. It provides a secure way to verify the identity of NHIs using hardware-backed security mechanisms. This approach ensures that the identity is tied to the hardware, making it much harder to spoof or compromise.

Hardware-attested identity leverages the device's hardware to verify its identity. Devices with Android 7.0 (API level 24) or higher can use key attestation to ensure keys are stored in hardware-backed keystores, according to Android Developers. (Verify hardware-backed key pairs with key attestation | Security)

This involves verifying the certificate chain to ensure the root certificate is trusted. For instance, the root certificate should come from Google or a trusted third party. This process ensures that the device hasn't been tampered with.

As we explore the role of hardware-attested identity, we'll see how it can provide a more secure foundation for managing NHIs in modern IT environments.

What is Hardware-Attested Identity?

Is your non-human identity truly secure, or is it just a house of cards waiting to fall? Hardware-attested identity offers a way to anchor trust in the physical hardware itself, providing a more robust foundation for authentication.

At its core, hardware attestation relies on hardware-backed key storage. This means cryptographic keys are stored in secure hardware like Trusted Execution Environments (TEEs), Secure Enclaves, or Hardware Security Modules (HSMs). These environments are designed to resist tampering and unauthorized access, providing a secure vault for sensitive keys.

The process involves several critical steps. First, a key pair is generated within the secure hardware. Next, an attestation certificate is obtained, which vouches for the key's origin and properties. Finally, the certificate chain is verified, ensuring it traces back to a trusted root of trust.

Diagram 1

Attestation serves a vital role in verifying the integrity of both the device and its software environment. By confirming that the hardware and software haven't been compromised, it establishes a strong basis for trust. This is especially critical in industries like finance, where secure transactions depend on trustworthy devices.

The keystore is a fundamental component. It acts as a secure repository for storing cryptographic keys, preventing unauthorized access. This is essential for protecting NHIs, as it ensures their keys aren't exposed to software vulnerabilities.

Attestation certificates are structured in the X.509 format, containing specific extensions that detail the key's properties and origin. These certificates include an attestation extension, which provides verifiable information about the key's security characteristics. Examining the certificate, security teams can verify its authenticity and trustworthiness. Some examples of security characteristics that might be found in such an extension include: presence of a hardware security module (HSM), confirmation of a secure boot status, or details about the device's hardware model.

A trusted root certificate authority (CA) is crucial for verifying the attestation chain. The root CA acts as an anchor of trust, ensuring that the entire chain is legitimate. Certificate Revocation Lists (CRLs) also play a role, identifying certificates that have been compromised and should no longer be trusted.

How Hardware-Attested Identity Works for NHIs

Hardware-attested identity isn't just a concept; it's a practical approach to securing Non-Human Identities (NHIs) in real-world scenarios. Let's explore how this technology works in practice.

The journey of a hardware-attested NHI begins with establishing its initial identity, a crucial step that anchors trust in the hardware itself.

Binding Identity to Hardware: The NHI's identity is intricately linked to its underlying hardware during manufacturing or provisioning. This process generates unique cryptographic keys stored securely within the device's hardware-backed security module. Think of it as embedding the NHI's digital DNA directly into its physical being.
Role of Manufacturers and Cloud Providers: Device manufacturers or cloud providers play a pivotal role in provisioning these initial attestation keys. They act as trusted authorities, ensuring that the keys are generated and stored securely. This might involve injecting keys into a Trusted Execution Environment (TEE) or using a Hardware Security Module (HSM) during the manufacturing process.
Secure Boot and Verified Boot: Secure boot and verified boot processes are paramount. These mechanisms ensure that only authorized software runs on the NHI, preventing malicious code from compromising the initial identity. Verified Boot establishes a chain of trust, verifying the integrity of each software component before it executes, as described by Android Developers. (Verify hardware-backed key pairs with key attestation | Security)

Once the NHI's identity is established, the next step is to ensure continuous trust during runtime.

Authentication with Hardware-Backed Keys: NHIs use their hardware-backed keys to authenticate to other systems, proving their identity in a secure manner. This involves cryptographic protocols that leverage the private key stored within the secure hardware.
Remote Attestation: A key process is remote attestation, where the NHI is challenged to prove its identity and integrity to a remote verifier. The NHI generates a signed attestation statement, which includes data about its current state and configuration.

Diagram 2

Access Control Decisions: The verifier uses the attestation data to make access control decisions. If the data indicates that the NHI is trusted and hasn't been tampered with, access is granted. Otherwise, access is denied, preventing potentially compromised NHIs from accessing sensitive resources.

Maintaining the security of hardware-attested identities requires robust certificate revocation and key rotation mechanisms.

Certificate Revocation: Certificate revocation is essential for handling compromised NHIs. If an NHI's private key is suspected of being compromised, its certificate can be revoked. This prevents the compromised NHI from being able to authenticate to other systems.
Key Rotation: Key rotation improves security by periodically replacing cryptographic keys. This reduces the impact of potential compromises, as an attacker would only have access to a key for a limited time.
Automated Key Rotation Strategies: Automated key rotation strategies are vital for managing NHIs at scale. These strategies involve automatically generating new keys and updating certificates on a regular basis, minimizing the administrative overhead. An example of an automated key rotation strategy could be periodic re-attestation with new key generation every 90 days.

Benefits of Hardware-Attested Identity for NHIs

Hardware-attested identity isn't just about security; it's about building a more trustworthy foundation for your entire IT infrastructure. Let's explore how it can revolutionize your approach to NHI management.

Hardware attestation significantly reduces common NHI security risks.

Mitigating Credential Theft: By anchoring identity to hardware, it becomes exponentially harder for attackers to steal or spoof credentials. Think of a point-of-sale (POS) system in retail; hardware attestation ensures that only legitimate devices can process transactions, preventing unauthorized access to sensitive financial data, as noted by Guardsquare.
Improved Security: Compared to software-based solutions, hardware attestation offers a far more robust line of defense. Software-based authentication can be bypassed with root exploits, but hardware-backed keys remain secure even if the operating system is compromised.
Resistance to Privilege Escalation: Hardware attestation makes it difficult for attackers to escalate privileges. For instance, in healthcare, a compromised server can't impersonate a critical service to access patient records if that service's identity is hardware-attested.

Meeting regulatory requirements becomes simpler with hardware-attested identities.

Meeting Compliance: Hardware attestation helps organizations meet stringent compliance requirements. For example, financial institutions can use it to comply with PCI DSS standards, ensuring that all NHIs handling cardholder data are properly secured.
Improved Auditability: Each NHI access and activity is easily auditable, providing a clear trail of actions. This is crucial for SOC 2 compliance, where demonstrating the security and integrity of systems is paramount.
Demonstrating Security: Hardware attestation allows organizations to demonstrate the security and integrity of NHIs to auditors. This can simplify the audit process and reduce the risk of non-compliance.

Managing NHIs at scale can be a daunting task, but hardware attestation can streamline the process.

Simplified Management: Hardware-attested identity can simplify NHI identity management at scale. Rather than juggling countless software credentials, you can rely on the immutable identity baked into the hardware.
Reduced Operational Overhead: The reduced operational overhead compared to traditional credential management can free up valuable resources. Key rotation and certificate management can be automated, reducing the burden on IT staff.
Centralized Policy Enforcement: Hardware attestation facilitates centralized policy enforcement and monitoring. This ensures that all NHIs adhere to the same security standards, regardless of their location or function. For example, an organization could enforce a policy that only NHIs attested to be running on specific, approved hardware models can access sensitive customer databases. Another policy might require all NHIs interacting with financial systems to undergo re-attestation every 30 days.

Real-World Use Cases

Hardware-attested identity isn't just a theoretical concept; it's rapidly becoming a cornerstone of real-world security strategies. Let's explore some specific use cases where hardware attestation is making a tangible difference.

Secure inter-service communication is critical in cloud environments. Hardware attestation ensures that only verified services can communicate with each other, preventing unauthorized access and lateral movement. For instance, a financial api can use hardware attestation to verify the identity of a microservice requesting transaction data, ensuring that sensitive information isn't exposed to compromised workloads.
Protecting containerized workloads and serverless functions is another key application. By attesting to the integrity of the underlying hardware, organizations can ensure that containers and functions haven't been tampered with. This is especially important in regulated industries like healthcare, where compromised workloads could lead to data breaches and compliance violations.
Enforcing zero-trust access policies becomes more robust with hardware attestation. Access decisions can be based not only on traditional factors like user roles but also on the hardware identity of the workload. This approach strengthens security by verifying the integrity of every access request, regardless of the user or application involved.
Securing IoT device onboarding and provisioning is a major challenge. Hardware attestation provides a secure way to verify the identity of IoT devices as they connect to the network, preventing rogue devices from gaining access. Think of smart city infrastructure; hardware attestation can ensure that only authorized sensors and controllers are integrated into the network, preventing malicious actors from disrupting critical services.
Verifying the integrity of IoT device firmware and software is essential for maintaining the security of these devices over their lifecycle. Hardware attestation can be used to ensure that firmware updates are authentic and haven't been tampered with. This is vital in industrial IoT (IIoT) environments, where compromised devices could lead to equipment damage or safety hazards.
Enabling secure communication between IoT devices and cloud platforms is crucial for data integrity and privacy. Hardware attestation ensures that data transmitted from IoT devices to the cloud is authentic and hasn't been intercepted or modified. This is particularly important in applications like remote patient monitoring, where accurate and reliable data is essential for effective care.
Verifying the identity of build agents and deployment tools is a key step in securing CI/CD pipelines. Hardware attestation ensures that only trusted agents and tools are used to build and deploy software, preventing malicious code from being injected into the process. This is crucial for preventing supply chain attacks, where attackers compromise the software development process to distribute malware.
Ensuring the integrity of software artifacts in the CI/CD pipeline is another important application. Hardware attestation can be used to verify the integrity of code, libraries, and other artifacts, preventing the deployment of compromised software. By attesting to the provenance and integrity of each component, organizations can build a more trustworthy software supply chain.
Preventing unauthorized code deployments and supply chain attacks is a top priority for security teams. Hardware attestation provides a robust mechanism for preventing unauthorized deployments, ensuring that only verified code is pushed to production environments. This helps to mitigate the risk of supply chain attacks and protect against malicious insiders.

Limitations of Software-Based Authentication

While software-based authentication methods have served us for a long time, they come with inherent weaknesses when it comes to securing Non-Human Identities (NHIs). Understanding these limitations is crucial for appreciating the value of hardware-attested identity.

Software-based authentication relies on credentials like passwords, API keys, and certificates that are stored and managed within the software environment. This makes them susceptible to a range of attacks:

Vulnerability to Compromise: Software is inherently more vulnerable to compromise than dedicated hardware. If an attacker gains access to the operating system or application layer, they can potentially steal, modify, or forge software-based credentials. This can happen through malware, phishing attacks, or exploiting software vulnerabilities.
Difficulty in Verifying True Identity: It's challenging to definitively prove that a software-based identity truly belongs to the intended entity. An attacker could potentially impersonate a legitimate NHI by replicating its software credentials, making it difficult for systems to distinguish between legitimate and malicious actors.
Susceptibility to Tampering: Software can be tampered with. An attacker could alter the code or configuration of an NHI to bypass security checks or grant unauthorized access. Without a hardware anchor, there's no reliable way to verify that the software hasn't been tampered with since its last known good state.
Scalability and Management Challenges: Managing a large number of software-based credentials for NHIs at scale is a significant operational burden. Ensuring proper rotation, revocation, and secure storage for each credential becomes increasingly complex and prone to human error.

These limitations highlight why a more robust approach is needed for securing NHIs in today's threat landscape.

Challenges and Considerations

Hardware-attested identity isn't without its hurdles. Let's examine some challenges and considerations to keep in mind when implementing this technology for Non-Human Identities (NHIs).

Opting for specific hardware attestation solutions could lead to vendor lock-in. Choosing solutions supporting open standards and interoperability is vital.
Consider the lifecycle management of hardware. Hardware refresh cycles can impact the continuity of NHI identities, demanding careful planning. For instance, when a device reaches its end-of-life, its NHI must be migrated or re-attested on new hardware to maintain uninterrupted service. This requires proactive planning for identity migration and re-attestation processes.
Selecting a hardware attestation solution requires a clear understanding of its dependencies and long-term maintainability.
Hardware attestation can introduce performance overhead. The attestation process adds latency to NHI operations, potentially impacting response times.
Optimizing attestation performance and minimizing latency is crucial. Strategies include caching attestation results and using efficient cryptographic algorithms.
Implementing hardware attestation solutions can be complex. It often requires specialized expertise in cryptography, hardware security, and identity management.
Integrating with existing identity management systems can be challenging. Planning and robust testing are essential for a smooth deployment.

Conclusion: The Future of NHI Security with Hardware-Attested Identity

Hardware-attested identity is more than a security feature; it's a paradigm shift towards verifiable trust in a world of increasingly sophisticated threats. How can organizations ensure the integrity of their Non-Human Identities (NHIs) in the face of evolving cyber risks?

Hardware attestation offers a robust means of securing NHIs, mitigating risks such as credential theft and privilege escalation. Compared to software-based methods, it provides a more secure foundation, anchoring trust in the physical hardware itself.
It serves as a foundational layer, complementing existing security measures like multi-factor authentication and intrusion detection systems. By verifying the integrity of NHIs at the hardware level, it strengthens the overall security posture.
Organizations should adopt hardware attestation as a core component of their NHI security strategy. By integrating it into their broader security architecture, they can improve the resilience of their systems and data.