5 Microsoft 365 Governance Gaps That Put Your Organisation at Risk

Governance in Microsoft 365 is not about permissions spreadsheets or quarterly audits. It is the set of structures, policies, and controls that determine how your organisation's data is stored, accessed, shared, and protected — and who is accountable for each of those things. When governance is absent or incomplete, the platform becomes a liability: data accumulates without structure, access expands without review, and the compliance posture degrades silently until an incident or an audit makes the gaps visible.

After assessing more than 50 Microsoft 365 environments across European mid-market organisations, the same five governance failures appear with striking consistency. None of them are edge cases. All of them are fixable.

Gap 1: Uncontrolled Teams and SharePoint Sprawl

What it looks like: Every user in the organisation can create a Microsoft Teams group, which automatically provisions a SharePoint site, a shared mailbox, a OneNote notebook, and a Planner board. Two years into deployment, the tenant has 400 Teams and 600 SharePoint sites, most of which are owned by people who have since left the company or forgotten they created them.

The risk: Orphaned Teams and sites accumulate files, conversations, and shared links without any owner to review or manage them. External guests who were invited for a single project remain in the tenant for years. Sensitive documents exist in channels that were never properly restricted. When you need to respond to a subject access request or a legal hold, you cannot tell where the data is.

What good looks like: Teams creation is governed — not blocked, but controlled. A request process (Approvals app or a simple Power Automate flow) captures the business purpose, assigns an owner, and applies naming conventions. Lifecycle management runs quarterly: owners receive a prompt to renew or archive. Inactive Teams are archived automatically after a defined period. Guest access has an expiry date. The tenant has a known, manageable number of active workspaces.

Gap 2: No Sensitivity Labels or Data Classification

What it looks like: Documents in SharePoint and OneDrive carry no classification. There is no distinction between a draft internal memo and a confidential board paper — both exist in the same unstructured state. When users share files externally, the platform cannot warn them that they are sharing something sensitive because it does not know.

The risk: Oversharing happens silently. Users share links because it is the easiest thing to do, not because they have considered whether the recipient should have access. Without classification, Data Loss Prevention policies cannot be targeted effectively. When Microsoft Copilot is introduced — and many organisations are planning to do so — it will surface documents based on permissions, not on whether those documents should be surfaced. Classification is the prerequisite that nobody has done.

What good looks like: A sensitivity label taxonomy defined in Microsoft Purview: at minimum, Public, Internal, Confidential, and Highly Confidential. Labels applied automatically to files meeting certain criteria (e.g. documents containing financial data, personal information, or commercially sensitive content) and manually by users for everything else. DLP policies that block or warn when Confidential or higher content is shared externally. This is a programme of work, not a one-day configuration change — but it starts with defining the taxonomy and training users.

Gap 3: Overprivileged Accounts

What it looks like: The IT team has global admin access on their primary accounts, which they use for daily email. Several users were given SharePoint admin rights for a migration project three years ago and still have them. Service accounts have user licences and global admin rights because that is what was easiest at the time.

The risk: Every overprivileged account is an attack surface. A compromised global admin account gives an attacker full control of the tenant — the ability to read all mailboxes, exfiltrate data, delete backups, and lock out the IT team. Most ransomware attacks against M365 tenants exploit privileged accounts, not technical vulnerabilities in the platform itself.

What good looks like: Least-privilege as a principle, not an aspiration. Global admin roles reserved for emergency break-glass accounts, protected with FIDO2 MFA and not used for daily work. Privileged Identity Management (PIM) in Entra ID for just-in-time elevation — admins request the role they need, it is granted for a defined period, and all activity is logged. Regular access reviews to clean up role assignments. Service accounts with only the permissions they actually need and no interactive sign-in rights.

Gap 4: Conditional Access Gaps

What it looks like: MFA is "enabled" in the legacy per-user settings, but there are no Conditional Access policies enforcing it. Or there are CA policies, but they contain legacy authentication protocol exceptions that were added during deployment and never removed. Or MFA is enforced for most users but not for service accounts, external guests, or users signing in from corporate network IP ranges.

The risk: Legacy authentication protocols bypass MFA. If SMTP AUTH, IMAP, or basic authentication are still enabled in your tenant, an attacker with a compromised password can access that account without triggering any MFA challenge. This is not theoretical — it is one of the most common initial access vectors in Microsoft 365 compromises. "We have MFA" is not a security posture if legacy auth is still open.

What good looks like: A baseline Conditional Access policy set: MFA required for all users (no exceptions for network location), legacy authentication blocked entirely, compliant device required for access to sensitive applications, high-risk sign-in and high-risk user policies integrated with Entra ID Identity Protection. These policies are reviewed quarterly, not set and forgotten. New exceptions require documented approval and an expiry date.

Gap 5: No Governance for External Sharing

What it looks like: External sharing in SharePoint is enabled at the tenant level with no restrictions. Users share files and folders using "Anyone with the link" links, which do not require sign-in and have no expiry. External collaboration happens through guest accounts that were never reviewed, some of whom belong to people who left their organisations months ago.

The risk: "Anyone" links are effectively public URLs. The file they point to can be accessed by anyone who obtains that link — forwarded in email, shared in a chat, or discovered by a search engine if the link is indexed. There is no audit trail of who accessed the file. For any organisation handling personal data, commercially sensitive information, or anything under a confidentiality obligation, this is a significant exposure.

What good looks like: External sharing configured at the most restrictive level that business requirements allow — typically "New and existing guests" rather than "Anyone". Anyone links disabled or limited to anonymous view with an enforced expiry. External guest accounts enrolled in access reviews: every six months, owners confirm whether guest access is still required. External sharing for sensitive data blocked via DLP policy. A regular report of active external links and guest accounts, reviewed by IT or compliance.

Governance Is a Programme, Not a Project

The five gaps above are common, but they share a root cause: Microsoft 365 governance was never treated as an ongoing programme. It was either not set up at all, or it was configured once during deployment and not revisited.

The organisations that maintain a clean M365 posture are not doing anything heroic. They run quarterly access reviews. They have a Teams lifecycle policy. They know how many external guests are in their tenant and why. They review their Conditional Access policy set when the threat landscape changes.

Governance is the difference between a Microsoft 365 environment that grows in control and one that grows in complexity. The good news is that the Microsoft platform provides most of the tools — the gap is almost always in configuration and process, not in capability.

If you want to understand where your organisation sits against these five benchmarks, a structured M365 governance assessment is the starting point. It takes two to three weeks and produces a prioritised remediation roadmap with the specific configuration changes required.