Your Microsoft 365 Environment Is Probably Misconfigured — Here's What to Check

Apr 4
4 min read

April 2026 | TAAUS Secure Technologies

If your organization uses Microsoft 365 — and the vast majority of businesses do — there's a good chance your environment is configured in a way that creates serious security exposure. Not because your IT team is careless. Because Microsoft 365 ships with default settings that prioritize ease of use over security, and most organizations never change them.

This isn't a theoretical risk. The Stryker cyberattack in March 2026 centered on a compromised Microsoft environment. The attackers didn't need sophisticated tools — they used legitimate Microsoft features against the company. That pattern repeats itself constantly, across organizations of every size, because the entry points are built into the platform by default.

Here's what executives and business owners need to understand about where their M365 environment is likely exposed — and what to ask their IT team or provider to check.

The Seven Areas Most Commonly Left Exposed

1. Multi-Factor Authentication is not enforced for all users. MFA is the single most effective control against credential-based attacks, and yet it remains optional in many M365 environments. Default settings don't require it. Organizations that enabled M365 before MFA enforcement became standard practice are frequently running with MFA turned on for some users but not others — or not at all. Every account, without exception, should require MFA. Privileged accounts should require phishing-resistant MFA such as hardware security keys.

2. Legacy authentication protocols are still enabled. Older email protocols like POP, IMAP, and SMTP AUTH don't support modern MFA. Attackers actively target these protocols specifically because they bypass multi-factor authentication entirely. If your organization has no legitimate need for these protocols — and most don't — they should be disabled. Leaving them on is the equivalent of adding a deadbolt to your front door while leaving a window unlocked.

3. Global administrator accounts are over-provisioned and under-protected. Global admin is the highest privilege level in M365. It grants complete control over your entire environment. Most organizations have more global admin accounts than they need, those accounts are often used for day-to-day tasks rather than reserved for administrative functions, and they're rarely governed by Privileged Identity Management — meaning the access is permanent rather than time-limited. The Stryker attack exploited exactly this configuration. One compromised global admin account was all it took.

4. External sharing in SharePoint and OneDrive is too permissive. By default, M365 allows users to share files externally with anyone — including people outside your organization who have no account and no verification requirement. In a law firm or financial services context, this means client documents, deal files, and privileged communications can be shared with an external link that anyone with the URL can access. External sharing settings should be reviewed and restricted to match your actual business needs.

5. Email security settings are not fully configured. M365 includes a range of email security features — anti-phishing policies, Safe Links, Safe Attachments, DMARC/DKIM/SPF authentication — that are either disabled or set to minimum protection levels by default. Organizations running M365 without Defender for Office 365 properly configured are relying on baseline email filtering that misses a significant volume of modern phishing and business email compromise attempts.

6. Audit logging is not enabled or retained long enough. M365 audit logging is not enabled by default in all license tiers, and where it is enabled, the default retention period is often too short to support a meaningful incident investigation. If your environment is breached, audit logs are how you reconstruct what happened, when, and what was accessed. An organization without adequate logging can't answer those questions — which means it can't contain the breach, can't meet regulatory notification requirements, and can't prevent recurrence.

7. Conditional access policies are absent or minimal. Conditional access is what allows your M365 environment to evaluate the context of every login — device compliance, location, risk signals — and apply appropriate friction. Without it, a valid username and password from any device, anywhere in the world, gets straight through. With it, an unusual login triggers additional verification or an outright block. For most organizations, this is the difference between a stolen credential being a minor incident and a catastrophic one.

What to Ask Your IT Team or Provider

You don't need to be technical to hold your IT team or managed service provider accountable for these controls. Here are the questions worth asking:

Is MFA enforced for every user in our M365 environment, including shared and service accounts?
Are legacy authentication protocols disabled?
How many global administrator accounts do we have, and when were they last reviewed?
What are our current external sharing settings in SharePoint and OneDrive?
Is Defender for Office 365 configured, and are our anti-phishing policies active?
Is audit logging enabled, and how long are logs retained?
Do we have conditional access policies in place, and what do they cover?

If your IT team can't answer these questions clearly and confidently, that's important information. It means either the controls aren't in place, or the visibility isn't there — both of which represent real exposure.

This Is Not a Technology Problem

The M365 misconfiguration problem isn't fundamentally about technology. It's about the gap between deploying a platform and securing it — a gap that exists in most organizations not because anyone made a bad decision, but because nobody was specifically responsible for closing it.

Microsoft provides the tools. Configuring them correctly, keeping them current, and ensuring they're aligned with your actual risk profile requires ongoing attention that goes beyond standard IT support. For most professional services firms, that means either a dedicated security function or a cybersecurity partner who can own it on their behalf.

The good news is that the controls described above are not complex or expensive to implement. They are, however, easy to overlook — and attackers are counting on that.

TAAUS conducts Microsoft 365 security configuration reviews for financial services firms, law firms, and healthcare organizations. If you're not sure whether your environment is configured securely, schedule a consultation and we'll help you find out.