Harnessing Security by Adopting Zero Trust Architecture

Over the past several years, Zero Trust Architecture (ZTA) has gained increased interest from the global information security community. Over the years, several organizations have adopted Zero Trust Architecture (ZTA) and experienced considerable security improvements. One such example is Google, which implemented a BeyondCorp initiative embodying ZTA principles. The tech giant removed trust assumptions from its internal network, focusing instead on verifying users and devices for every access request, regardless of their location. This transformation has allowed Google to offer its workforce more flexibility while maintaining robust security. 

We also see relevant guidelines emerging from commercial entities and government bodies. Specifically, a memorandum was released detailing recommendations for US agencies and departments on how to transition to a "Zero Trust" architecture. 

Let's delve into a brief overview of ZTA.

Key Considerations in Adopting a Zero Trust Architecture

The core idea of this architecture is not to mindlessly trust any entity, system, network, or service, whether they are within or outside the security perimeter. Instead of granting access freely, every interaction should be rigorously checked. This marks a significant shift in the way we approach the protection of our infrastructure, networks, and data: from a single perimeter check to a continuous, detailed inspection of every device, user, application, and transaction. This ensures that the targeted information system always possesses comprehensive information about the party involved during the authentication/authorization phase.

Furthermore, applications should not depend on network perimeter security to prevent unauthorized access. Users should log directly into applications and not entire networks\systems. In the immediate future, we should consider every application as potentially accessible over the Internet from a security standpoint. As organizations adopt this mindset, it is anticipated that the requirement to access applications through specific networks will no longer be necessary.

Numerous tools can assist with ZTA implementation, such as network security solutions like Next-Generation Firewalls (NGFWs), Secure Access Service Edge (SASE), and Identity and Access Management (IAM) software. Additionally, resources like NIST's SP 800-207 Zero Trust Architecture document can provide further in-depth understanding and guidelines for ZTA adoption.

Several approaches to building a ZTA exist advanced identity management, logical micro-segmentation, and network-based segmentation. All approaches aim to isolate systems as much as possible so that an attacker who compromises one app cannot travel within the organization and compromise other sectors.

The transition of an organization to Zero Trust Architecture (ZTA) looks like this:

• The process of managing employee accounts ensures they have all the necessary resources to perform their duties while following the principle of least privilege. 
• The devices that employees utilize for their job tasks are under constant supervision and control. The security status of these devices (configuration, patch level, integrity, etc.) plays a significant role when it comes to granting access to internal resources. 
• The organization's systems are kept isolated from one another, and any network traffic circulating between or within these systems is both encrypted and authenticated. 
• Applications used within the enterprise undergo both internal and external testing.  
• Platforms such as GitLab are essential for upholding the top standards of DevSecOps principles. 
• The organization's security teams are responsible for establishing data categories and setting security rules in order to automatically identify and prevent any unauthorized access to sensitive information.

The transition to ZTA should be considered through the prism of the following key areas: identities, devices, networks, applications, and data. Let's briefly review each of them.

Identities 

A centralized identity management system needs to be implemented across the organization. It is crucial to apply robust multi-factor authentication (MFA) throughout the enterprise. When granting users access to resources, at least one device-level signal should be taken into account, along with the authenticated user's identity information. The level of risk associated with accessing an application from a specific corporate network should be seen as no less than accessing it from the Internet.

Devices

The organization must keep a comprehensive inventory of all authorized devices currently in use. Moreover, it is vital that the organization can effectively prevent, detect, and respond to any incidents involving these devices.

Network

Organizations should aim to encrypt all traffic whenever possible, even when data travels within internal networks and client portals. It is important to actively use strong encryption protocols like TLS 1.3. The underlying principles of these protocols should be taken into account, especially for minimizing the number of long-term keys. A leak of any of these keys could pose a significant risk to the entire system's operation.

Applications

Organizations need to operate dedicated programs for testing application security. In case of a shortage of expertise, it is always a good idea to seek high-quality, specialized software testing services for independent third-party evaluations of application security. It is crucial for organizations to manage a responsive and open public vulnerability disclosure program. While deploying services and products, organizations should strive to use immutable workloads, especially when dealing with cloud-based infrastructure.

Data

It is vital to set up defenses that utilize comprehensive data categorization. Leverage cloud security services and tools to identify, classify, and safeguard your sensitive data while also implementing logging and information sharing across the entire enterprise. Companies should try to automate their data categorization and security responses, particularly when regulating access to sensitive information. Regularly audit access to any data that is at rest or while it is being transmitted on commercial cloud infrastructure. 

Common Challenges and Solutions

The transition to ZTA is not without its hurdles. One significant challenge is the potential for increased complexity and operational overhead. Managing numerous security configurations, encryption protocols, and access control lists can be daunting. However, automated security solutions and centralized management systems can help streamline the process and reduce human error.

Another common issue is resistance to change within the organization. The shift to ZTA can be disruptive, requiring changes in company culture and workflows. This challenge can be mitigated through comprehensive training programs, clear communication about the benefits of ZTA, and gradual implementation strategies.

Conclusion

Traditional security architectures operate on the assumption that all data and transactions are secure by default. Yet, incidents such as data breaches and other compromises can shatter this trust. Zero Trust Architecture revolutionizes this trust model, starting with the presumption that all data and transactions are potentially untrustworthy right from the outset.

Adopting ZTA provides numerous benefits, such as improved security posture, reduced risk of data breaches, and flexibility in accommodating remote work or BYOD policies. However, it does come with potential drawbacks. The cost and complexity associated with the initial implementation can be high, and there is the risk of potential service disruption during the transition. To mitigate these drawbacks, companies considering ZTA should begin by assessing their current security posture and then identifying areas where ZTA principles could be initially applied while also building a roadmap for a full transition.