Microsoft 365 Security Audit
Your Microsoft 365 environment works. But is it truly secure?
Most organizations use Microsoft 365 every day for email, files, and collaboration. But few have verified that their configuration actually protects their data.
A Microsoft 365 (M365) security audit helps identify:
- vulnerabilities
- misconfigurations
- invisible risks within your environment
Before an incident reveals them for you.
A functional environment doesn’t mean a secure one
Most Microsoft 365 environments work just fine day-to-day. But several weaknesses remain invisible until they’re exploited:
- Overly permissive access that gives certain users more rights than they need
- Multi-factor authentication (MFA) missing or incomplete on critical accounts
- Poorly controlled external sharing that exposes files without anyone knowing
- Security settings available in the licence — but never activated
These risks don’t trigger alerts. They don’t cause outages. They sit there, silent, until an attacker finds them.
Why have your Microsoft 365 environment audited
The goal of an audit isn’t to change everything. It’s to move from a functional environment to a controlled one.
An audit allows you to:
- Identify concrete security vulnerabilities in your current configuration
- Understand the real risks your organization is exposed to
- Prioritize fixes based on their impact
- Structure your environment to reduce the attack surface
An audit is particularly useful after a migration to Microsoft 365, during a change in IT personnel, after rapid user growth, or simply if no one has done one in more than a year.
What we analyze: more than 100 control points
The Rhesus team performs an in-depth analysis of your M365 environment, covering more than 100 critical elements grouped into six categories.
Access and identities
Troubleshooting and optimization of computers and user workstations.
Environment security
Organizational settings, security alerts, detection of risky activities. We ensure that the protections available in your licence are actually activated.
Email protection
Anti-phishing configuration, attachment filtering, compliance policies. Email remains the number one attack vector.
Applications and external access
Third-party applications connected to your environment, granted permissions, OAuth access. Entry points that are often overlooked.
Data and sharing
SharePoint and OneDrive permissions, external sharing links, files publicly accessible without reason.
Usage and environment
Global view of connected devices, Teams configuration, risky behaviours detected in activity logs.
What you receive after the audit
The audit concludes with a clear report designed to be understood by decision-makers, not just technicians.
The report includes:
- The overall risk level of your environment
- Detailed findings, ranked by priority
- Immediate recommendations to apply
- A structured action plan to address the identified weaknesses
You’ll know exactly what to fix — and in what order. No unnecessary jargon, no vague recommendations.
After the audit: next steps
The audit is the starting point. Once the findings are in hand, Rhesus can support you through implementation:
- Optimizing your Microsoft 365 environment based on audit recommendations
- Advanced security: conditional access policies, email protection, automated alerts
- Device management with Microsoft Intune to control access from workstations and mobile devices
- Continuous monitoring with our managed IT services to detect abnormal behaviour in real time
Why trust Rhesus with your audit
Rhesus is a managed IT services and cybersecurity firm supporting businesses across Quebec. With more than 80 IT professionals and offices in Victoriaville, Sherbrooke, and Mirabel, our team handles both prevention and incident response.
Our Microsoft 365 audit is conducted by specialists who know Microsoft environments from the inside — because they manage and secure them every day for dozens of organizations.
If a critical vulnerability is identified during the audit, our team can intervene immediately. No need to find another vendor.
Frequently Asked Questions: Microsoft 365 Security
What is a Microsoft 365 (M365) security audit?
It’s a full analysis of the configurations, access settings, and security parameters of your Microsoft 365 environment. The Rhesus team verifies more than 100 control points to identify vulnerabilities and risks.
How long does a Microsoft 365 audit take?
Duration varies depending on the size of the environment, but the audit is generally completed within a few days. The analysis is non-intrusive and does not disrupt your operations.
Will the audit interrupt our activities?
No. The audit is performed without any service interruption. Your team continues to work normally throughout the entire analysis.
Is it necessary if we already have an internal IT team?
Yes. An external review validates the configurations currently in place and identifies blind spots that an internal team may not catch on a day-to-day basis. It’s the same principle as a financial audit: you have someone independent verify what’s there.
What happens if critical vulnerabilities are found?
Rhesus notifies you immediately and can step in to address the most urgent issues. You won’t be left alone with a report — our team supports you through the implementation of corrections.