Introduction to Zero Trust Security Model

Zero Trust is a security framework based on the principle of "never trust, always verify.” However, the misrepresentation and misinterpretation of the concept's workings in the real world starts here. Instead of removing all trust,  understand it is as default deny. 

Zero trust stands to three key principles, which are:

• Zero Implicit Trust – Always authenticate and authorize based on all available data, including user identity, device health, and location.
• Ephemeral Trust-  Grant only the minimum access necessary( JEA- Just Enough Access) and for the shortest time required (JIT- Just In Time).
• Assume Breach Mindset – Design security controls with the assumption that breaches will happen, enabling rapid detection and response.

Zero trust is an evolving concept as organizations operate across multiple environments—on-premises, cloud, hybrid, and multi-cloud—creating complexities in securing access to critical assets. Neil MacDonald,  a distinguished VP analyst at Gartner, emphasizes, “Zero Trust is not a technology; it’s a security philosophy that rewires how we think about access.” A zero-trust framework ensures that security policies are enforced uniformly across all environments, minimizing the risk of data breaches.

Evolution of Zero Trust Security

Before the 2000s, security relied on perimeter-based defenses, assuming internal systems were inherently trustworthy. However, the rise of remote work and public Wi-Fi blurred traditional boundaries, leading organizations to adopt corporate VPNs for secure access.

In 2004, the Jericho Forum introduced deperimeterization, advocating for layered security with encryption and data-level authentication. Paul Simmonds, who coined the term, emphasized the shift from rigid staff classifications to a more complex security landscape.

In 2010, John Kindervag of Forrester pioneered the Zero Trust model, replacing outdated trust assumptions with a "never trust, always verify" approach. Zero Trust reduces risk and strengthens security by enforcing strict identity verification and least-privilege access. Organizations like NIST and the U.S. Department of Defense later adopted and popularized the framework.

With the surge in ransomware, supply chain attacks, and insider threats, Zero Trust has become essential for modern cybersecurity. Recognizing this, President Biden issued an Executive Order on January 16, 2025, mandating federal agencies to implement Zero Trust within 180 days.

The order emphasizes continuous access validation, network segmentation, phishing-resistant MFA, and stronger endpoint detection. It also requires third-party software providers to meet stringent security standards, reinforcing national cybersecurity resilience.

The Need for Zero Trust in Application Security

Zero Trust's primary goal is to protect data and sensitive information from unauthorized access, breaches, and cyberattacks, such as:

Ransomware Attacks

Ransomware attacks, where threat actors encrypt data and demand payment for its release, have surged in recent years. Traditional security models often fail because attackers exploit compromised credentials or move laterally within a network.

The Colonial Pipeline ransomware attack (2021) was facilitated by a compromised VPN password that lacked multi-factor authentication (MFA). A zero-trust approach could have mitigated this by enforcing least privilege access, continuous authentication, and network segmentation, preventing attackers from spreading across the infrastructure.

Supply Chain Attacks

Cybercriminals increasingly target third-party vendors to infiltrate organizations, as seen in high-profile supply chain breaches. Zero Trust mandates strict access control and continuous monitoring of all external entities interacting with critical systems.

The SolarWinds attack (2020) allowed attackers to inject malicious updates into widely used network monitoring software, compromising thousands of organizations. 

Insider Threats

Employees, contractors, or partners with malicious intent—or even those who inadvertently expose sensitive data—pose a significant cybersecurity risk. Zero Trust reduces this risk by ensuring that no user has unrestricted access to critical systems and that all activities are monitored and logged.

In the 2023 Tesla insider data leak, an employee stole confidential information, including customer and employee data. 

Challenges with Traditional Security Approaches

Legacy security models primarily rely on firewalls, VPNs, and static access controls, creating significant security gaps like:

Implicit Trust Within Networks

‍Traditional security assumes that authenticated users or applications can be trusted throughout the session. This allows attackers to move laterally within the network if they gain access.

Static Perimeters‍

Firewalls and perimeter-based defenses were designed for on-premises environments. Static perimeters fail to provide adequate protection as businesses transition to the cloud and multi-cloud environments.

Overprivileged Access

‍Many applications grant excessive permissions, increasing the risk of credential abuse, privilege escalation, and data breaches.

With modern application development, security risks have increased due to various factors:

APIs as a Primary Attack Vector‍

APIs connect applications, services, and third-party systems, but weak authentication, misconfigurations, and unencrypted data transfers expose them to cyberattacks. API flaws account for 11.8% of all cyber abuse.

Cloud-Based Applications

‍Organizations operate in multi-cloud and hybrid environments, making enforcing consistent security policies and detecting unauthorized access difficult.

Third-Party Integrations‍

Enterprises rely on third-party applications for business operations. A single compromised integration can be an entry point for attackers to infiltrate an entire system.

How Zero Trust Principle Supports Application Security

Zero Trust is based on Verify Explicitly, Enforce Least Privilege, and Assume Breach. These ensure continuous security, controlled access, and breach resilience, making them essential for applications and APIs.

Verify Explicitly

Zero Trust continuously verifies users, devices, applications, and data instead of relying on location or one-time authentication. Access requests are authenticated and authorized based on identity, device security, and behavior.

• MFA adds an extra layer of verification beyond passwords.
• Continuous session validation re-evaluates access based on risk factors like location or device changes.
• Use OAuth 2.0, JWTs, or API keys to ensure only authorized clients interact with APIs.
• Behavior-based access detects anomalies (e.g., rapid data requests) and dynamically revokes or revalidates access.

Enforce Least Privilege Access

Users, devices, applications, and APIs should have only the minimum access needed, reducing security risks.

• RBAC & ABAC grant access based on roles or attributes like department or location.
• API scope restrictions limit API permissions to specific data or actions (e.g., a payment API can only process a user’s transactions).
• Time-Limited Access (JIT) provides temporary permissions (e.g., a developer gets API access for 1 hour).
• Microservices Segmentation restricts service permissions (e.g., a service that reads orders shouldn't delete them).

Assume Breach

Zero Trust assumes attackers will gain access, so security must detect, contain, and minimize damage.

• API rate limiting & anomaly detection block suspicious spikes in API requests (e.g., brute-force or data scraping).
• Micro-segmentation limits lateral movement by restricting access between application components.
• Logging & monitoring tracks API requests, failed logins, and data transfers for real-time threat detection.
• Automated Incident Response immediately revokes access, isolates workloads, or alerts admins upon detecting threats.

Zero Trust Architecture for Applications

Identity and Access Management (IAM) Features

IAM is the foundation of Zero Trust, ensuring that only authenticated and authorized users, applications, and devices can access resources.

• Multi-Factor Authentication (MFA): Adds an extra layer of security beyond passwords. For example, if a Salesforce employee logs in from an unrecognized device or location, Salesforce prompts for additional authentication, such as biometric verification or a one-time password (OTP).
• Single Sign-On (SSO): Enables secure authentication while reducing password fatigue. For example, Bank of America customers can log in using a secure authentication portal with Single Sign-On (SSO), allowing them to access multiple banking services (e.g., checking accounts, investments, loan applications) without various logins.
• Role-Based Access Control (RBAC) & Attribute-Based Access Control (ABAC): Grants access based on user roles and contextual attributes (e.g., location, device trust).
• Just-In-Time (JIT) Access: Provides temporary permissions instead of persistent ones, reducing exposure.

‍Micro-Segmentation Strategies

Micro-segmentation divides an application into isolated segments, restricting lateral movement within an environment.

• Service-to-Service Segmentation: Limits communication between application services, ensuring one compromised service does not affect the entire system.
• Network-Level Segmentation: Uses software-defined perimeters (SDP) to isolate workloads and prevent unauthorized access.
• Zero Trust Network Access (ZTNA): Ensures only authenticated users can access microservices, regardless of network location.

Children’s Mercy, a pediatric medical center in Kansas City, faced challenges with unmanaged medical devices and unclear role allocations across departments. Leadership implemented micro-segmentation, grouping, and securing medical devices while assigning roles to address this. This resulted in a risk-scored inventory, the elimination of outdated processes, and the reorganization of staff responsibilities using security group tagging. Additionally, automated security policies ensured that only authorized personnel, such as medical billing clerks, could access sensitive patient data, strengthening overall cybersecurity.

‍Secure API Gateways Key Measures

Since APIs serve as a critical attack vector, secure API gateways enforce Zero Trust policies at the application level.

• OAuth 2.0 & OpenID Connect: Ensures APIs authenticate requests securely.
• Rate Limiting & Throttling: Prevents API abuse and denial-of-service (DoS) attacks.
• Data Encryption & Tokenization: Protects sensitive API payloads.
• Runtime Protection: Detects and blocks malicious API activity.

A banking API uses JWT-based authentication to ensure secure access, requiring clients to include a valid token in each request. It enforces strict rate limits to prevent brute-force attacks, restricting the number of requests per client and blocking excessive attempts. If the limit is exceeded, the API returns a 429 Too Many Requests response, ensuring system stability and protecting user accounts from abuse.

‍Continuous Monitoring and Analytics Key Features

A Zero Trust application continuously monitors user activity, network traffic, and API interactions to detect anomalies and potential threats.

• Behavior-Based Anomaly Detection: Uses AI/ML to detect unusual patterns, such as sudden mass data exfiltration.
• SIEM (Security Information & Event Management) & SOAR (Security Orchestration, Automation, and Response): Aggregates logs and automates threat response.
• Threat Intelligence Integration: Identifies known attack signatures and indicators of compromise (IoCs).

A SaaS analytics platform integrates with a SIEM tool to detect unusual login behavior, such as an account suddenly accessing data from multiple geolocations.

‍Integration with Cloud-Native Technologies & CI/CD Pipelines

Modern applications operate in cloud-native environments and require security automation within CI/CD pipelines to enforce zero-trust principles from development to deployment.

• Infrastructure as Code (IaC) Security: Enforces least privilege in cloud resources (e.g., AWS IAM policies).
• Automated Security Scans in CI/CD Pipelines: Detects vulnerabilities before deployment.
• Container & Kubernetes Security: Enforces runtime security and network segmentation in microservices-based architectures.
• Serverless Security: Ensures functions (e.g., AWS Lambda) have minimal permissions to perform their tasks.

A DevOps team integrates security policies into CI/CD pipelines, automatically scanning new application builds for vulnerabilities before deploying to production.

Best Practices for Implementing Zero Trust

Implementing Zero Trust requires continuous authentication, monitoring, and risk minimization. Below are key best practices to secure applications effectively.

Enforce Multi-Factor Authentication (MFA) & Strong Identity Verification

Cybercriminals increasingly exploit valid credentials—accounting for 30% of security incidents in 2023. MFA mitigates this risk by requiring additional verification:

• Require MFA for all users, admins, and privileged accounts (e.g., Okta, Microsoft Entra ID, Duo Security).
• Use biometrics or hardware security keys (e.g., YubiKey, Face ID, Windows Hello). Mastercard Biometric Card combines chip technology and fingerprint authentication for secure in-store purchases.
• Implement risk-based authentication that triggers additional verification for unusual logins.

Implement Runtime Protection & Web Application Firewalls (WAFs)

Applications face SQL injection, XSS, and API abuse. Protect them using:

• Runtime Application Self-Protection (RASP): Monitors app behavior and blocks threats (e.g., Imperva RASP, Contrast Security).
• WAFs: Filters malicious HTTP requests (e.g., AWS WAF, Cloudflare WAF, Akamai Kona).
• Virtual patching to protect against zero-day vulnerabilities before fixes are available.

An e-commerce platform may use Cloudflare WAF to block DDoS attacks and Imperva RASP to prevent API abuse.

Integrate Security into DevOps & CI/CD Pipelines

Security must be automated within development to prevent slowdowns:

• Shift security left by integrating static security testing into CI/CD pipelines (e.g., Snyk, GitHub Advanced Security). Spotify integrated Snyk into its build pipeline, automating vulnerability scans to scale securely.
• Use Infrastructure as Code (IaC) policies for automated security enforcement (e.g., HashiCorp Sentinel, Terraform Compliance).
• Restrict permissions for DevOps tools (e.g., GitHub Actions, Jenkins, GitLab CI/CD). 

Leverage AI/ML for Threat Detection & Incident Response

Manual detection fails against evolving attacks—AI/ML enhances security by identifying anomalies in real-time:

• AI-driven behavior analytics to detect insider threats (e.g., Exabeam, Microsoft Defender for Identity).
• ML-based anomaly detection to track unusual API traffic (e.g., AWS GuardDuty, Splunk User Behavior Analytics).
• Automated incident response with SOAR platforms (e.g., Palo Alto Cortex XSOAR, IBM Resilient).

Papa Johns’ CITO credits Splunk for helping the company react dynamically to evolving cyber threats.

Secure APIs & Monitor Application Dependencies

80% of web traffic is API-based, making APIs a prime attack target. Strengthen API security with:

• API gateways enforcing authentication & rate limits (e.g., Kong Gateway, Apigee, AWS API Gateway).
• Logging & anomaly detection to track suspicious access patterns (e.g., Datadog API Security, Traceable AI).
• Third-party dependency scanning to prevent supply chain attacks (e.g., OWASP Dependency-Check, Mend).
• Software Bill of Materials (SBOM) to track dependencies (e.g., CycloneDX, Syft).

Many fintech companies use Datadog API Security Monitoring to block unauthorized API calls.

Challenges in Implementing Zero Trust & How to Overcome Them

Implementing Zero Trust Architecture (ZTA) presents challenges, including high costs, integration complexity, and organizational resistance. Here’s how to overcome them:

High Costs & Resource Demands

Zero Trust requires significant investment in technology, training, and personnel. To reduce costs:

• Implement phased adoption, starting with MFA and API security.
• Leverage existing security tools (IAM, SIEM, endpoint security) instead of replacing them.
• Use cloud-native security services (e.g., Azure AD, AWS IAM, Okta) instead of expensive on-prem solutions.
• Show ROI by demonstrating how preventing a significant breach offsets costs.

Integration Complexity with Legacy Systems

Zero Trust must work across legacy apps, hybrid clouds, and multiple identity providers, leading to operational challenges. Solutions include:

• Gradual integration instead of a complete system overhaul.
• Implement unified access through SSO & Identity Federation (SAML, OAuth 2.0, OpenID).
• Use API gateways (Apigee, AWS API Gateway, Kong) to enforce Zero Trust on legacy applications.
• Deploy Zero Trust orchestration platforms (Illumio, Zscaler, Palo Alto Prisma) for simplified policy enforcement.

Resistance to Change

Employees and IT teams may resist stricter access controls. To ease adoption:

• Educate staff on security benefits while ensuring minimal workflow disruption.
• Use adaptive authentication (e.g., MFA prompts only for high-risk logins).
• Engage leadership by showcasing compliance benefits (e.g., NIST 800-207, CISA Zero Trust Model).
• Create a Zero Trust champion team to drive awareness and support adoption.

Future Trends in Zero Trust and Application Security

Quantum Computing & Zero Trust

Quantum computing threatens traditional encryption, making quantum-resistant security essential. Future adaptations include:

• Adoption of NIST’s Post-Quantum Cryptography (PQC) standards for quantum-safe encryption.
• Quantum Key Distribution (QKD) is used to secure communications.
• Automated key rotation & dynamic encryption to stay ahead of quantum threats.

Google & IBM are already working on quantum-safe encryption to future-proof Zero Trust.

AI-Driven Threat Detection & Adaptive Zero Trust

Cyberattacks are becoming more sophisticated, requiring AI-powered defenses:

• AI anomaly detection will analyze user behavior, API traffic, and network activity in real-time.
• Adaptive Zero Trust will dynamically adjust access controls based on risk levels.
• AI-powered SOAR platforms (e.g., Microsoft Defender, CrowdStrike) will automate real-time threat mitigation.

Zero Trust for IoT & Edge Computing

With IoT and edge computing expanding, Zero Trust must extend beyond traditional networks:

• Device authentication (e.g., hardware-based authentication, certificates) before granting access.
• Micro-segmentation at the edge to isolate compromised IoT devices and prevent lateral movement.
• 5G-native security controls to protect data at the network edge.

The U.S. Department of Defense has adopted Zero Trust to secure military IoT systems.

Zero Trust & DevSecOps Integration

Security must be built into fast-paced CI/CD pipelines without slowing innovation:

• Security as code policies automate Zero Trust enforcement from development to deployment.
• Infrastructure-as-code (IaC) principles prevent unauthorized cloud workload changes.
• Automated security testing (SAST, DAST, SCA) ensures Zero Trust compliance in CI/CD workflows.

GitHub Advanced Security & Snyk integrate Zero Trust scanning into CI/CD, detecting vulnerabilities before deployment.

Case Study: Zero Trust Implementation in Canadian Airlines

WestJet’s Zero Trust Transformation

In 2015, WestJet, one of Canada’s largest airlines, adopted Forrester’s Zero Trust Model to modernize its security infrastructure. Traditionally, companies relied on perimeter-based security, assuming everything inside the corporate network was safe. However, WestJet recognized that insider threats, phishing attacks, and advanced persistent threats (APTs) required a more robust approach.

To address these risks, WestJet implemented Zero Trust principles, including:

• Network Segmentation: Instead of a single trusted internal network, WestJet segmented access to ensure that employees, applications, and systems only had access to the necessary resources.
• Identity and Access Management (IAM): Multi-factor authentication (MFA) and strict role-based access were enforced to prevent unauthorized access.
• Continuous Monitoring: Advanced logging, anomaly detection, and AI-driven analytics were introduced to identify and mitigate potential threats in real time.

This transition improved security and allowed WestJet to modernize its IT infrastructure, enabling greater flexibility in adopting cloud services and remote work solutions.

Conclusion

Implementing Zero Trust in application security is no longer optional; it is necessary in today’s evolving threat landscape. With traditional perimeter-based security models proving insufficient, Zero Trust ensures continuous verification, least privilege access, and micro-segmentation to minimize attack surfaces and limit potential damage.

CIOs should start ZTA with high-impact areas such as multi-factor authentication (MFA), identity and access management (IAM), and API security, then expand to runtime protection, DevSecOps integration, and AI-driven threat detection. A phased approach helps mitigate high costs, integration complexity, and resistance to change. Leveraging existing security investments and cloud-native solutions can also ease the transition.

As cyber threats grow more sophisticated, Zero Trust must evolve. Future advancements will include quantum-resistant encryption, AI-powered anomaly detection, and Zero Trust for IoT and edge computing. CISOs that embed Zero Trust principles into their DevSecOps workflows will gain agility, security, and resilience against emerging threats.

Ultimately, Zero Trust is not a one-time deployment but an ongoing security strategy. By continuously monitoring, adapting policies, and leveraging automation, businesses can fortify their applications against cyberattacks and ensure long-term data protection, compliance, and operational efficiency.

Strengthen your defenses with Zero Trust. At Cogent Infotech, our cybersecurity experts can help you fortify your applications and data against modern threats. Connect with us today to discover how Zero Trust principles can transform your security posture.