Attestation-Based Access Control for Non-Human Identities

Understanding Non-Human Identities and Their Security Challenges

Did you know that non-human identities (NHIs) are quietly revolutionizing how systems communicate and operate? However, this rise in machine-to-machine interactions introduces new security challenges that demand a focused approach.

NHIs are digital identities used by applications, services, and devices to interact with each other and access resources. They come in many forms, including:

• Service Accounts: Used by applications to access databases or other services. For instance, a retail application might use a service account to access inventory data.
• Workload Identities: Used in cloud environments like AWS, Azure, or Google Cloud to grant permissions to applications running within containers or VMs.
• Device Identities: Represent IoT devices, such as medical devices in healthcare or point-of-sale systems in retail, each requiring secure access to networks and data. According to Apple, device attestation provides strong evidence about which properties of a device can be used as part of a trust evaluation. This is especially important in industries that rely heavily on IoT devices.
• Robotic Process Automation (RPA) Bots: These bots automate tasks across different systems, requiring access to various applications and data sources.

Securing NHIs presents unique challenges:

• Identity Sprawl: The sheer number of NHIs can be overwhelming.
• Lack of Visibility: Unlike human users, NHIs often operate behind the scenes, making them harder to monitor.
• Over-Privileged Access: NHIs are often granted broad permissions, exceeding what they actually need.
• Attestation: According to a ServiceNow Community post, attestations are surveys that gather evidence to prove that a control is implemented. This ensures that controls are not only in place but also effective.
• Key Management: Managing and rotating keys and secrets for NHIs can be complex and prone to errors.

As NHIs become more prevalent, a robust security strategy is essential. This is where attestation-based access control comes into play, offering a powerful solution to verify the trustworthiness of these identities.

In the next section, we'll explore what attestation-based access control is and how it works.

What is Attestation-Based Access Control?

Did you know that unauthorized access by non-human identities (NHIs) is a growing concern for organizations? Attestation-based access control offers a robust solution by verifying the trustworthiness of these identities before granting access.

Attestation-based access control is a security mechanism that validates the integrity and trustworthiness of an NHI before it's allowed to access resources. It works by gathering evidence about the NHI’s identity, configuration, and runtime environment, then comparing this evidence against a set of predefined policies. If the NHI meets the required criteria, it's granted access; otherwise, access is denied. According to One Identity, identity and access attestation is a process that involves verifying and validating the identity of individuals and managing their access to systems, applications or resources within an organization.

• Evidence Collection: This involves gathering data about the NHI, such as its software version, configuration settings, and security posture. For device attestation, as mentioned earlier, properties of a device can be used as part of a trust evaluation.
• Policy Definition: Organizations define policies that specify the required attributes and conditions for an NHI to be considered trustworthy. These policies might include factors like compliance with security standards, the absence of malware, or adherence to specific configurations.
• Attestation Verification: The collected evidence is compared against the defined policies. This process often involves cryptographic techniques to ensure the integrity and authenticity of the evidence.
• Access Control Enforcement: Based on the attestation results, access control decisions are made. NHIs that pass attestation are granted access, while those that fail are denied or given limited access.
• Continuous Monitoring: Attestation isn't a one-time event. Continuous monitoring ensures that NHIs remain compliant with security policies throughout their lifecycle.

Consider a cloud-based service account used by a financial institution. Attestation-based access control could verify that the service account is running the correct version of its application, has the necessary security patches installed, and is operating within a secure environment.

NHI->>AttestationService: Request Access Token
AttestationService->>NHI: Request Evidence
NHI->>AttestationService: Provide Evidence (e.g., TPM measurements)
AttestationService->>AttestationService: Verify Evidence against Policy
alt Attestation Successful
    AttestationService->>NHI: Issue Access Token
    NHI->>ResourceServer: Request Resource with Access Token
    ResourceServer->>ResourceServer: Validate Access Token
    ResourceServer->>NHI: Grant Access
else Attestation Failed
    AttestationService->>NHI: Deny Access Token
    NHI->>NHI: Access Denied
end

By implementing attestation-based access control, organizations can significantly reduce the risk of unauthorized access and improve their overall security posture. Next up, we'll dive into the various attestation methods and technologies available.

Attestation Methods and Technologies

Ever wondered how attestation goes from theory to reality? It's all about the methods and technologies that power this security mechanism.

Several attestation methods exist, each with unique characteristics and use cases. Understanding these differences is key to choosing the right approach for your non-human identities (NHIs).

• Hardware-Based Attestation: This method relies on hardware security modules (HSMs) or Trusted Platform Modules (TPMs) to provide a root of trust. These hardware components generate and store cryptographic keys, ensuring the integrity of the attestation process. For example, Azure Attestation supports attestation of platforms backed by TPMs, providing proof of a platform's state.
• Software-Based Attestation: This approach uses software to verify the integrity of an NHI. It typically involves measuring the software's code and configuration, then comparing these measurements against a known good baseline. While flexible, it can be more susceptible to tampering than hardware-based methods.
• Remote Attestation: This method involves a trusted third party verifying the integrity of an NHI. The NHI provides evidence about its state to the third party, which then assesses the evidence against predefined policies.
• Platform Attestation: As mentioned earlier, properties of a device can be used as part of a trust evaluation. Apple devices use platform attestation to ensure that only devices meeting certain hardware requirements are issued attestations.

Various technologies support attestation-based access control, making it easier to implement and manage.

• TPMs (Trusted Platform Modules): TPMs are hardware chips that provide secure storage for cryptographic keys and enable hardware-based attestation. They're commonly used in laptops, servers, and IoT devices.
• HSMs (Hardware Security Modules): HSMs are dedicated hardware devices that provide a secure environment for cryptographic operations. They are often used in financial institutions and other high-security environments.
• Azure Attestation: This Microsoft service provides a unified solution for remotely verifying the trustworthiness of a platform and the integrity of binaries running inside it. As previously discussed, it supports attestation of various environments, including TPMs and SGX enclaves.
• ACME (Automated Certificate Management Environment): ACME is a protocol for automating the issuance and management of digital certificates. As noted earlier, Apple devices can use ACME payload attestation to enroll a client certificate identity, which can cryptographically validate that the device is a genuine Apple device.

In the automotive industry, hardware-based attestation using TPMs can ensure the integrity of software updates in connected vehicles. This prevents malicious actors from injecting malware through compromised updates.

By understanding the various attestation methods and technologies, organizations can build robust security strategies for their non-human identities. Next, we'll delve into implementing attestation-based access control for NHIs.

Implementing Attestation-Based Access Control for NHIs

Implementing attestation-based access control for non-human identities (NHIs) might seem daunting, but with a strategic approach, it can significantly enhance your security posture. Let's break down the essential steps to get you started.

1. Identify NHIs: Begin by cataloging all NHIs within your environment. This includes service accounts, workload identities, and device identities. Understanding the scope is crucial for effective implementation.

2. Define Attestation Policies: Create clear policies that outline the required attributes and conditions for an NHI to be considered trustworthy. These policies should align with your organization's security standards and compliance requirements. For example, policies might specify acceptable software versions or require the absence of known vulnerabilities.

3. Choose Attestation Methods: Select the appropriate attestation methods based on your NHIs and infrastructure. Hardware-based attestation, as mentioned earlier, offers a strong root of trust, while software-based attestation provides flexibility.

4. Implement Attestation Technologies: Integrate technologies like TPMs, HSMs, or services such as Azure Attestation to collect and verify evidence about NHIs. Azure Attestation, as previously discussed, provides a unified solution for verifying platform trustworthiness.

5. Automate the Process: Automate evidence collection, policy evaluation, and access control enforcement to ensure continuous monitoring and consistent application of attestation policies. Automation minimizes manual effort and reduces the risk of human error.

Implementing attestation-based access control requires careful planning and execution.

• Start Small: Begin with a pilot project involving a subset of NHIs to test and refine your implementation. This allows you to identify potential issues and optimize your approach before a full-scale rollout.
• Continuous Monitoring: As One Identity explains, attestation and identity governance ensure that users can continue performing their jobs through changes in their authorization to access information, data and resources.
• Integrate with Existing Systems: Integrate attestation-based access control with your existing identity and access management (IAM) systems to streamline operations and avoid creating silos.

Consider a healthcare provider using medical devices (device identities) to collect patient data. By implementing attestation-based access control, the provider can ensure that only authorized and verified devices can access sensitive patient information. The attestation process could verify device integrity, software versions, and security configurations, preventing unauthorized access and data breaches.

By following these steps and tailoring your approach to your specific environment, you can successfully implement attestation-based access control and significantly improve the security of your NHIs.

Next, we'll explore some specific use cases where attestation-based access control can be particularly beneficial.

Use Cases for Attestation-Based Access Control

Ever wondered how attestation-based access control plays out in the real world? The possibilities are vast, and the security enhancements are significant across various sectors.

• Attestation-based access control is ideal for securing workload identities in cloud environments. For instance, a microservice in a financial application can use attestation to prove it's running in a secure, compliant environment before accessing sensitive customer data.

• In DevOps pipelines, attestation ensures that only verified and trusted code deployments are executed. This prevents malicious code injections and maintains the integrity of the software supply chain.

• Azure Attestation, as previously discussed, plays a critical role in verifying the trustworthiness of platforms and binaries, ensuring that cloud workloads operate within a secure and compliant environment.

• Attestation is crucial for IoT device security, especially in industries like healthcare. Medical devices can attest to their integrity before transmitting patient data, ensuring that only verified devices are communicating sensitive information. As mentioned earlier, Apple devices use platform attestation to ensure that only devices meeting certain hardware requirements are issued attestations.

• In industrial IoT (IIoT), attestation can verify the integrity of manufacturing equipment, preventing unauthorized access and tampering that could lead to production disruptions or safety hazards.

• Confidential Containers can use attestation to prove they are running in a trusted execution environment (TEE), isolating them from the control plane and other containers. Azure Attestation supports attestation for confidential containers, ensuring that sensitive data remains protected within these isolated environments.

• Attestation can be integrated into Kubernetes to verify the integrity of container images before deployment. This ensures that only trusted and verified containers are running within the cluster, reducing the risk of supply chain attacks.

• As noted earlier, Apple devices can use ACME payload attestation to enroll a client certificate identity, which can cryptographically validate that the device is a genuine Apple device. This ensures that only trusted devices are issued certificates, reducing the risk of unauthorized access.

• Attestation can automate the certificate renewal process for NHIs, ensuring that certificates are only renewed if the NHI meets the defined security policies. This reduces the risk of expired or compromised certificates being used for unauthorized access.

These use cases demonstrate the versatility and importance of attestation-based access control in securing non-human identities.

Up next, we'll explore the benefits of attestation-based access control and see how it can significantly enhance your organization's security posture.

Benefits of Attestation-Based Access Control

Want to fortify your security? Attestation-based access control offers numerous benefits, making it a powerful tool for securing non-human identities (NHIs).

• Reduced Unauthorized Access: By verifying NHI trustworthiness before granting access, attestation minimizes the risk of breaches.

• Improved Compliance: Attestation helps meet regulatory requirements by ensuring NHIs adhere to security policies. As mentioned earlier, One Identity explains that attestation and identity governance ensure that users can continue performing their jobs through changes in their authorization to access information, data and resources.

• Increased Trust: Knowing NHIs are continuously validated builds confidence in your systems.

• Automated Access Control: Attestation automates access decisions, reducing manual intervention.

• Real-time Monitoring: Continuous monitoring ensures NHIs remain compliant, triggering alerts for deviations.

• Centralized Policy Management: Define and enforce policies from a central location.

Consider a manufacturing plant using IIoT devices. Attestation ensures only verified equipment accesses the network, preventing malicious intrusions.

Despite these benefits, implementing attestation-based access control has challenges that we'll discuss in the next section.