The zero-trust security model has been attracting considerable attention in recent years, but it's not really something new. It was already gaining significant momentum before the pandemic and long before the White House incorporated it into the nation's overall cybersecurity strategy.
According to IBM, the approximate cost of a data breach is about $4.24 million. As such, the stakes are higher than ever before, and small and medium-sized businesses must take proactive steps to fortify their infrastructure and stay a step ahead of threat actors.
The good news is that the accelerated adoption of hybrid working models and the growing reliance on cloud technology is rapidly making "zero-trust" the de facto security posture at digitally transformed organizations.
What is Zero Trust?
Just like the name implies, the zero-trust framework follows an implicit trust philosophy and commands us to "trust no one." This is a significant departure from traditional security models that followed a "trust but verify" approach.
With this type of traditional approach to IT security, users and endpoints within the perimeter are automatically simply trusted, increasing the risk of insider threats, unauthorized access, and lateral movement. As digital transformation and public cloud adoption increases, this old-school approach to cybersecurity just falls short.
In contrast, the zero-trust security model requires continuous authentication, authorization, and validation of all internal and external users to gain and maintain secure zero-trust network access to apps and data on an enterprise network.
Whether it's on a public cloud or an on-premises data center, your zero-trust strategy must include the following zero-trust principles:
- Believe that "inside the network" doesn't exist
- Keep security policies clear and adaptive to the evolving threat level
- Trust nothing; verify everything!
The zero-trust model assumes that there isn't a traditional network edge. As such, it's the perfect security framework for securing modern infrastructure and data in digitally transformed enterprise environments.
For example, the zero-trust approach adequately addresses security challenges like cloud security, remote working, malware attacks, and ransomware attacks. The best approach here is to use zero-trust network access (ZTNA) tools for seamless network access management.
Zero trust methodologies also complement various security standards and compliance models, including the National Institute of Standards and Technology 800-207 (NIST 800-207) and Service Organization Control 2 (SOC 2).
What is Zero-Trust Network Access?
According to Gartner, ZTNA solutions help create an identity- and context-based logical access boundary. Think of it as a network perimeter around an enterprise app or set of apps. This approach helps keep apps hidden from discovery while restricting access to a group of named entities through a trust broker.
In this case, the broker will verify the identity and analyze end-user context and policy adherence before enabling access to the network. ZTNA removes application assets from public visibility, prohibits lateral movement, and reduces the attack surface.
How Does Zero Trust Work?
To execute the zero-trust model, security teams must first combine various tools for maximum effect. For example, organizations must leverage next-generation endpoint security, multi-factor authentication (MFA), virtual private networks (VPNs), identity protection protocols, single sign-on (SSO) tools, encryption tools, cloud workload management protocols, and much more.
By design, the zero-trust architecture demands continuous monitoring and validating to ensure that end-users and their devices only access data and applications they need to get the job done. In this scenario, security teams must enforce cybersecurity policies that consider both user and device access to enterprise infrastructure, regulatory compliance, and other industry-specific requirements.
The first step in the process is to identify all services and privileged accounts and establish access controls individually. At this juncture, it's important to note that user attributes and the latest threats will keep changing, making on-time validations futile and even obsolete.
By gaining complete real-time visibility into the environment, security teams can quickly identify:
- Applications installed on endpoints
- Authentication protocol and risk
- Different operating systems and patch levels
- Endpoint hardware type and function
- Firmware versions
- Geo locations
- Individual credential privileges
- User identity and types of credentials (programmatic or human)
- User and device behavior over standard connections
- Security event recognitions or incident detections
The zero-trust approach leverages automation by incorporating artificial intelligence (AI) and machine learning (ML), analytics solutions, and threat intelligence to enable hyper-accurate policy response.
The following is a brief look at steps to implementing a zero-trust model across your enterprise network.
7 Strategies to Implement a Zero-Trust Security Model
1. Map Hybrid Environments
As the attack surface expands exponentially (driven by the internet of things and hybrid cloud environments), we can't really keep up with the evolving threat landscape and ensure network security.
The zero-trust journey starts with security teams thoroughly assessing and identifying potential cyber attack paths and limiting exposure to a possible security breach. They can do this through network segmentation and by segmenting device types, group functions, or identities.
If you're not sure about what's protected on your network, you can't understand your current security posture. Whenever this is the case, your zero-trust implementation will lead to a significant waste of resources and time.
2. Determine Critical Process Flows
It's important because it's increasingly difficult to establish a protect surface in today's modern, digitally transformed infrastructure. Before establishing rules, policies, and purchasing tools to enforce them, it's always best to assess all process flows and pathways across apps, devices, services, and users.
Ask questions like, what do my employees need to work productively and efficiently? How can we fortify our security posture without impacting user experience?
It's vital to only provide access to data and applications your staff needs to get the job done. By leveraging robust access management solutions, security teams can minimize the attack surface and prevent lateral movement.
For example, there is no need for your sales team to have access to human resources applications or data. In the same vein, your sales team in America may not need access to the Canadian sales team's data. During an active security breach, you will be thrilled that you took the least privilege access approach.
3. Create Policies and Rules to Govern the Microperimeter
Once you have mapped your pathways and process flows, you can start defining the protect surface. You can set up rules and policies to govern the network perimeter, achieving greater granularity across endpoints.
As zero-trust concentrates on the micro-level of the attack surface, you can easily define your protect surface. Often, the protect surface comprises business-critical applications, sensitive data, digital assets, and services.
By mapping traffic flows across your network, you'll have a better idea of how you can secure it. It's critical to gain contextual insights into essential applications and data interdependencies. You can adequately enforce secure access controls while optimizing operations by correctly documenting them.
Some examples of what you'll find on a protect surface include personally identifiable information (PII), protected health information (PHI), and intellectual property (IP). Once you define the protect surface, you can move access and security controls as close as possible to the attack surface. This approach helps establish a microperimeter with limited policy statements that are precise and easily understandable.
Security teams must engage all key stakeholders across the organization to ensure that the most appropriate policies are enforced and that the staff are educated about them.
4. Deploy a Next-Generation Firewall
Support your zero-trust strategy with a next-generation firewall that works like a micro-segmentation gateway. Building a microperimeter around the protect surface enables the enforcement of additional layers of access control to thoroughly inspect anything attempting to access network resources within the microperimeter.
5. Formulate a Robust Zero-Trust Policy
Once your security team architects the network, you have to create and enforce zero-trust policies. The best approach here is to whitelist which resources should have secure access to others following the "Kipling Method."
The Kipling Method is named as such because the concept of "who, what, when, where, why, and how" was first put forth by the renowned author and poet, Rudyrad Kipling, in his poem "Six Serving Men." When applied to your cybersecurity strategy, you must ask questions such as:
- Who has permission to access a particular resource?
- When will they access the resource?
- Where is the packet destination?
- How does the packet access the protect surface through different applications?
- Why is a packet attempting to access resources within the protect surface?
- What applications should staff use to access resources within the microperimeter?
Whenever organizations follow the Kipling Method to granular policy enforcement, only known and legitimate traffic and applications will be allowed to communicate on the network.
6. Continuously Monitor and Enforce Zero-Trust Architecture
Modern cybersecurity protocols and strategies are proactive. It's the only way to mitigate risk at a time when data breaches hog the headlines. Support your zero-trust approach with dynamic governance and real-time monitoring.
At this juncture, you can enforce your rules and policies at the microperimeter and deploy your zero-trust network architecture. However, it's important to note that this process is time- and resource-intensive, so make sure to plan accordingly.
It's necessary to leverage AI- and ML-powered solutions to monitor your zero-trust network in real-time. As it's humanly impossible to observe everything around the clock, it's critical to leverage smart monitoring solutions to flag suspicious behavior in real-time and optimize cyber defenses.
Using security information and event management (SIEM), security teams can also gain a comprehensive understanding of security events collected across the applications, devices, and systems.
7. Create a Culture of Security and Accountability
For the zero-trust model to work, you need a collective effort from across the organization. All the effort made by the IT and security teams will only come to fruition if all stakeholders are on the same page. Senior leadership and executive buy-in will be crucial to properly implement zero-trust strategies into existing and future security strategies.
It's essential to establish clear and transparent responsibilities in different parts of the zero-trust framework. Keeping all expectations realistic when implementing the zero-trust model is also important. The best approach here is to encourage security- and non-security-focused teams to work closely to identify and rectify potential vulnerabilities. It's the best approach to early detection and prevention of catastrophic security events.