Zero Trust vs. least privilege: What's the difference?

Managing access to network assets is a critical part of cybersecurity. Two concepts constantly arise when discussing access management: Zero Trust and the principle of least privilege.

These are more than just buzzwords. What do these terms mean, and why are they vital in modern cybersecurity? Just as importantly, are Zero Trust and least privilege separate concepts or part of a larger whole?

This blog will explore how the principles differ and help you understand the conceptual basis of secure network access.

What is Zero Trust?

Zero Trust is a strategic security approach that follows the principle "never trust, always verify.”

In cybersecurity, organizations implement this principle via a set of technologies known as Zero Trust Network Access (ZTNA).

The Zero Trust concept requires a default position of mistrusting all connection requests and internal network activity. Every user and connection poses a potential threat. Systems should only grant access when organizations know for sure users are legitimate.

ZTNA’s main role is safeguarding work-related assets. For example, systems block access requests to documents from unauthorized devices or unusual locations. ZTNA technologies deny access to attackers with stolen credentials, keeping sensitive data safe.

The Zero Trust model departs from traditional security concepts by operating at the network edge and within the network perimeter.

• Only trusted users can enter the network perimeter. Identity verification happens via credential authentication and tools like device posture checks.
• Network managers monitor user activity within the network boundary. Access control measures block resources without appropriate permissions.
• Zero Trust architecture involves continuous security measures. Security tools monitor users continuously, requesting identity verification for each access request.

The idea behind Zero Trust is simple. With ZTNA safeguards in place, businesses make it harder for attackers to move within the network. By enforcing strict verification at each access point, ZTNA helps block any unauthorized access attempts.

Access controls and monitoring shrink the attack surface, limit lateral movement, and give security teams time to take quarantine measures.

The ZTNA framework evolved to suit modern business needs. The rise of distributed workforces and cloud computing made traditional perimeter defense obsolete. Identity-based security makes more as network boundaries become increasingly vague.

What is the principle of least privilege?

The principle of least privilege (PoLP) is related to privilege management.

PoLP requires network admins to limit the devices or applications users can access. Users should only enjoy access to resources they need to carry out authorized tasks.

Companies often apply PoLP via role-based access control (RBAC) measures. For example, medical researchers may need access to data sources and reports relevant to their research. Physicians should have access to individual medical records but may not need access to aggregated medical data. This approach ensures that each role has only the permission necessary for its specific responsibilities.

In other cases, PoLP applies dynamically, using just-in-time access, where permissions are granted only for a limited period. For example, DevOps teams at financial institutions may need to escalate privileges for database maintenance temporarily.

With just-in-time access, teams receive the necessary permissions only for the duration of the task, and access to confidential records is automatically revoked once the specific period ends. This way, sensitive access is strictly limited to when it’s needed, reducing long-term exposure to potential security risks.

Least privilege access allows teams to carry out maintenance tasks, before revoking access to confidential records when the task is done.

PoLP aims to reduce the harm caused by malicious actors by minimizing user privileges at all times. If cyber attackers breach network defenses, the principle of least privilege limits their access to sensitive data and critical systems.

When properly applied, PoLP ensures that users only have minimal permissions necessary for their roles. This means that even if attackers gain control of a user’s device, they’ll face restrictions on what actions they can take, reducing the risk of major data breaches or unauthorized access to critical information.

Cutting data breach risks has another important benefit. The principle of least privilege aids compliance with regulations like GDPR, PCI-DSS, and HIPAA. Companies handling confidential information can limit access to those with a legitimate business reason - in line with regulatory requirements.

Least privilege access applies to all network users, from junior staffers to administrators. Nobody should have the freedom to roam across all network resources. Controls include non-human users such as APIs and virtual machines as well.

Privileged access applies to all users within the network directory, requiring a comprehensive analysis of network resources and user identities. Admins must assign privileges accurately and update access rights as needed.

Zero Trust vs. least privilege

The principle of least privilege and ZTNA play complementary roles in digital security architecture, but their scope and how they handle security risks differ.

Let's start with the similarities. Both frameworks aim to protect data and shrink the attack surface.

ZTNA and least privilege access also use similar tools to achieve this goal. Both frameworks advise using identity and access management (IAM) systems, segmentation, and network monitoring.

Are there any important differences between ZTNA and least privilege access?

ZTNA and least privilege are far from identical. However, the key takeaway is the two concepts complement each other in network security setups.

The Zero Trust model is concerned with how organizations authorize user activity. ZTNA-based systems authenticate users, discovering whether they are who they claim to be. Systems verify identities whenever they receive access requests. As a result, ZTNA is generally more resource-intensive and complex. Security teams must verify every activity and access request.

Least privilege access focuses narrowly on how users relate to network assets. In this sense, the principle of least privilege is an essential component of all Zero Trust solutions.

Applied on its own, PoLP is a useful foundation for data protection and privileges management. However, ZTNA delivers greater in-depth protection to meet urgent security needs.

Should you choose between Zero Trust and least privilege models?

The key takeaway is this: There is no natural opposition between Zero Trust vs. least privilege concepts.

Most companies would benefit from using both approaches when designing security measures. PLOP and ZTNA are critical components of Defense-in-Depth (DiD) strategies. You can't lock down data effectively without considering both frameworks.

Companies can choose how extensively they deploy Zero Trust and least privilege-based access controls. However, in-depth access controls are vital in a world of endemic data breaches and phishing threats.

Key components of Zero Trust and least privilege

Robust network security setups leverage Zero Trust Network Access and the principle of least privilege to safeguard resources. We generally find the following components in both security models:

• Network asset classification. Companies must identify critical assets before defining access rights. Admins identify assets requiring protection, including data storage, applications, and hardware systems. Access policies define user permissions, enabling precise access control measures.
• Access controls at the network edge. Traditional access controls filter requests at the network edge. Tools like multi-factor authentication (MFA) and next-generation firewalls admit legitimate users and block unauthorized access requests.
• Software-defined perimeters. ZTNA deployments often use a software-defined perimeter (SDP) that accommodates today's flexible network architecture. SDP verifies user identities via credentials, posture checks, and data like user location and access times. Users can then access approved resources without the need for add-ons like VPNs or wholesale network access.
• Identity and Access Management. Privileged access tools assign permissions, determining which resources users can access and the types of activity they can carry out. For instance, some users may have read privileges, while access rights for others include editing or deleting data.
• Network segmentation. Network segmentation divides network resources by robust internal walls. Admins define segments via firewalls, software-defined networking (SDN), access control lists, or a combination of measures.
• Network monitoring. The Zero Trust security models require continuous monitoring of access requests. Systems must check device statuses, user activity, and network traffic patterns. Monitoring ensures users remain at the appropriate privileged access level. Alerts also allow rapid responses to potential data breaches.
• Threat response. Security teams must shrink the attack surface rapidly when attacks materialize. Zero Trust security advises companies to plan for worst-case scenarios and adopt a proactive approach to quarantining threats.

How do ZTNA and least privilege fit into security systems?

PoLP and ZTNA security measures often complement Virtual Private Networks (VPNs) and encryption to maximize security. VPNs allow remote workers to connect securely and anonymously. ZTNA and least privilege controls limit their access to relevant resources, adding another layer of security protection.

Zero Trust security may also form part of Secure Access Service Edge (SASE) solutions. In this case, adaptive ZTNA controls work with next-generation firewalls and software-defined networking to defend network resources.

SASE is a good model for globally distributed remote workforces. It does not rely on fixed infrastructure or single work locations. Identity verification occurs wherever users connect, so you may not need legacy tools like VPNs.

How NordLayer can help

Implementing Zero Trust solutions or the principle of least privilege can be challenging.

Zero Trust requires companies to cover every asset and user, install reliable monitoring and authentication systems, and handle lengthy periods of disruption. PoLP requires tight privileges management and access controls.

The good news is that expert partners like NordLayer help you manage these problems.

Nordlayer enables you to create virtual private gateways to safeguard access to your sensitive resources, enhanced by additional layers of security.

For example:

• The Cloud Firewall enables easy network segmentation to strengthen resource protection.
• IAM solutions like multiple MFA options, single sign-on (SSO), and user provisioning ensure identities are triple-checked.
• Robust network access control measures such as Device Posture security make sure that only authorized devices or users from allowed locations can connect to the network.

NordLayer can help with whichever approach you adopt. We provide a simple route to implement Zero Trust and the principle of least privilege. To find out more, contact our team to arrange a demo today.