Zero trust is a security model based on a simple yet powerful premise: no user, device, or system should be automatically trusted, regardless of whether they are inside or outside the corporate network.
In a corporate context, compromised credentials are one of the most common attack vectors, hybrid environments expose data to multiple access points, and employees work from anywhere; therefore, operating with implicit trust is no longer acceptable.
According to the Microsoft Digital Defense Report, Microsoft infrastructure records over 600 million identity attacks per day, and more than 99% of compromised accounts did not have multi-factor authentication enabled.
In this article, you will understand how the zero trust model works, why so many companies still operate without it, and how to implement it practically within the Microsoft 365 ecosystem. Read on.
For decades, corporate security was built on perimeter logic: everything inside the network is safe, everything outside is a threat. Firewalls, VPNs, and location-based access controls formed the barrier that separated the trusted environment from the outside world.
This model worked well while data lived on local servers and employees worked only from the office.
However, the corporate environment has changed profoundly. Applications have migrated to the cloud, teams have shifted to remote work, vendors and partners access internal systems, and personal devices connect to corporate networks without any formal control.
In this context, the perimeter is no longer an effective barrier, and the traditional model creates a false sense of security; once an attacker obtains valid credentials, they walk right through the front door and move through the environment with almost unrestricted freedom.
The zero trust model addresses this problem by replacing location-based trust with continuous, context-based verification.
Every access request, from any user, on any device, from any location, is treated as potentially untrustworthy and evaluated in real time based on multiple factors before being granted.
This way, even if a credential is compromised, the attacker encounters additional barriers at every stage of the environment.
Imagine a mid-sized company that has been using Microsoft 365 for three years. Employees access email, SharePoint, and Teams with just a username and password, without mandatory multi-factor authentication.
A service provider who worked on a project last year still has an active account in the environment. An employee receives a convincing phishing email, clicks the link, and enters their credentials on a fake page.
Within minutes, the attacker is inside the environment with access to everything that employee can access, without a single alert being triggered.
This scenario is not hypothetical. According to the IBM Cost of a Data Breachreport, the global average cost of a data breach has reached $4.45 million, and companies with a zero trust model in place reduced this cost an average of $1.76 million per incident.
In other words, beyond being a security issue, it is a financial decision.
The most concrete risks of operating with implicit trust include:
· Unrestricted lateral movement: an attacker who compromises an account with broad access can move between systems, files, and applications without encountering additional barriers, expanding the impact of the incident far beyond the initial point of compromise.
· Orphaned identities and privilege creep: employees who have changed departments or left the company often retain access that was never revoked, representing silent entry points that go unmonitored.
· Unmanaged devices as attack vectors: without device compliance policies, any endpoint, including personal mobile phones and outdated laptops, can be the starting point of a compromise.
· Lack of visibility into internal activity: without continuous monitoring of access and behavior, the company simply does not know what is happening within its own environment until the damage has already been done.
Implementing zero trust does not require replacing your entire existing infrastructure. To companies already using Microsoft 365, a good portion of the necessary tools is already available within the ecosystem itself, though often underutilized or misconfigured.
Microsoft Entra ID, formerly known as Azure Active Directory, is the central identity platform that enables the zero trust model within the Microsoft environment.
Shall we explore 3 fundamental features?
Instead of verifying the user only at login, zero trust continuously evaluates the context of every access request: who the user is, what device they are on, where they are accessing from, what time it is, and what behavior they are exhibiting.
Microsoft Entra ID performs this assessment in real time, applying conditional access policies that block, restrict, or require additional verification whenever a risk signal is detected.
Entra ID's conditional access allows you to create granular rules that define exactly the conditions under which access is permitted. For example, an employee accessing SharePoint from an unmanaged device outside of business hours may be prompted to complete additional authentication or have their access restricted to read-only mode.
Furthermore, the principle of least privilege ensures that each user accesses only what is strictly necessary for their role, drastically limiting the impact of any compromise.
MFA is one of the most impactful controls within the zero trust model, blocking the vast majority of attacks based on compromised credentials.
Microsoft Entra ID P1 and P2, available in Microsoft 365 Business Premium and Enterprise plans, offer advanced MFA, risk-based identity protection policies, and automatic detection of suspicious behavior, such as logins from impossible locations or unusual access patterns.
One of the most relevant points for managers and IT analysts is that most of the tools needed to implement zero trust are already included in the Microsoft 365 licenses that many companies pay for monthly.
The problem is rarely a lack of tools, but rather a lack of configuration and a partner who knows how to activate them correctly.
· Microsoft 365 Business Premium includes Microsoft Entra ID P1, Intune for device management, Defender for Business, and conditional access, covering the core layers of the zero trust model
· Microsoft 365 E3 adds advanced compliance, enhanced identity management, and Entra ID P1 for the entire organization
· Microsoft 365 E5 incorporates Entra ID P2 with risk-based identity protection, Defender XDR, and Microsoft Sentinel for real-time monitoring, reaching the most mature level of zero trust
However, having the license is not the same as having the model implemented. Misconfigured conditional access, MFA active only for some accounts, devices without compliance policies, and identities without periodic reviews are common situations in environments that have been paying for Microsoft 365 for years but still operate with implicit trust in practice.
Therefore, we emphasize that activating the available features and configuring them cohesively is what turns the license into real protection.
Frayha implements the zero trust model by leveraging the features that the Microsoft 365 ecosystem already offers—which many companies still do not fully utilize—as well as other market options for companies that desire them.
The first step is always the diagnostic: understanding how the environment is currently configured, which Microsoft 365 features are available but not yet activated, and what the most critical gaps are to be addressed.
From there, Frayha structures a progressive zero trust implementation roadmap, prioritizing maximum impact with the least operational friction for teams.
👉 Request a free diagnostic and discover how to make your company's security more solid and reliable.
Is zero trust a product you can buy?
No. Zero trust is a security model, a philosophy of how access to corporate resources should be granted and monitored. It is implemented through a set of tools, policies, and processes. In the Microsoft ecosystem, Microsoft Entra ID, conditional access, and Intune are the primary tools that enable the implementation of the model.
Do I need to replace my current infrastructure to adopt zero trust?
Not necessarily. For companies that already use Microsoft 365, much of the necessary infrastructure is already available. Zero trust implementation tends to be incremental, starting with identity controls and progressively expanding to device management, access segmentation, and continuous monitoring.
Is zero trust suitable for mid-sized companies or only for large corporations?
The zero trust model is suitable for any organization that relies on digital systems to operate, regardless of size. In fact, mid-sized companies are often more vulnerable targets precisely because they invest less in security than large corporations. Microsoft 365 Business Premium plans already include the core tools for the zero trust model, making implementation accessible for companies with smaller teams.
How long does it take to implement zero trust?
It depends on the current state of your environment and the defined scope. A progressive implementation, starting with critical controls like MFA and conditional access, can have a significant impact in just a few weeks. Evolving to more advanced controls, such as risk-based identity protection and network segmentation, typically happens in phases over several months without disrupting daily business operations.
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