+44 3301 333 307 magma@magmacloud.co.uk
Pillar 02

Microsoft 365 Security
& Hardening

Microsoft 365 ships configured for collaboration, not security. We close the gap — secure baselines, Conditional Access, Intune device compliance, Defender for Office 365, Teams governance, and DLP. For UK organisations that rely on M365 for everything.

From £TBC — fixed fee, scoped after your Ignite Assessment
The Challenge

M365 default settings optimise for usability, not security.

Microsoft 365 is the most widely deployed productivity platform in the UK — and one of the most consistently under-secured. The default configuration prioritises collaboration. That means legacy authentication enabled, MFA not enforced, external sharing open, Defender policies at minimum, no DLP, and Conditional Access either absent or poorly scoped. Attackers know this. Business email compromise, credential stuffing, and Teams-based phishing campaigns all exploit exactly these gaps.

There are over 40 policy areas to configure correctly in a modern M365 tenant. Most organisations have touched fewer than half of them. We work through every one systematically — understanding your business requirements, then building controls that protect without creating friction for your people. This is not generic advice; it's a hardening engagement that leaves your tenant measurably more secure.

What We Deliver

M365 Security Services

What we deliver
  • M365 secure baseline implementation
  • Conditional Access policy design & deployment
  • MFA enforcement & legacy authentication block
  • Intune & endpoint compliance policies
  • Defender for Office 365 — anti-phishing, safe links, safe attachments
  • SharePoint & Teams governance hardening
  • Email authentication: SPF, DKIM, DMARC
  • Data Loss Prevention (DLP) policies
  • BYOD & mobile device management
  • Microsoft Secure Score optimisation
Outcomes you can measure
  • Significantly improved Secure Score
  • Enforced MFA across all users
  • Legacy authentication blocked
  • Reduced phishing exposure
  • Controlled external sharing
  • DLP policies protecting sensitive data
  • Regulator-ready audit logging
How It's Delivered

The Magma Cloud Lifecycle

M365 hardening delivered in phases to avoid disruption — assessment first, then implementation, then continuous monitoring and posture management.

01
Strategy
02
Assess
03
Implement
04
Optimise
05
Manage
06
Assure
Related Security Services
Common Questions

Frequently Asked Questions

No. M365 is configured for collaboration by default, not security. Without active hardening — Conditional Access policies, MFA enforcement, Defender for Office 365 configuration, DLP rules, and external sharing controls — your tenant has significant gaps that attackers regularly exploit. Business email compromise and credential phishing campaigns specifically target default M365 configurations.

We implement the Microsoft Secure Score baseline across your tenant — Conditional Access policies, MFA enforcement, legacy authentication blocking, Defender for Office 365 anti-phishing and safe links, SharePoint and Teams external sharing controls, DLP, email authentication (SPF, DKIM, DMARC), and Intune device compliance. We work through all 40+ policy areas systematically.

Only if your data permissions are correctly configured first. Microsoft Copilot respects your existing M365 permissions — if users have access to sensitive SharePoint sites, mailboxes, or documents they shouldn't, Copilot will surface that data in its responses. Our AI Security service covers the permissions audit, sensitivity labelling, and DLP controls needed before you safely enable Copilot for your organisation.

A focused M365 security hardening engagement typically runs two to four weeks depending on tenant complexity, number of users, existing licensing tier, and any legacy systems or third-party integrations. We work in phases to avoid disrupting your people and roll out Conditional Access policies in report-only mode first so you can review the impact before enforcement.

Plan 1 gives you anti-phishing, safe links, and safe attachments — the essential protection layer. Plan 2 adds attack simulation training, threat hunting, automated investigation and response (AIR), and the Threat Explorer. Which you need depends on your risk profile, size, and regulatory environment. We'll recommend the right licence tier as part of your Ignite Assessment — and we'll never recommend more than you actually need.

Start with a Free
Ignite Assessment

The Ignite Assessment

A free 30-minute call with a senior security architect. For M365, you leave with a read of your current Secure Score gaps, the top three hardening priorities, and a clear view of whether and how we can help. No pitch deck, no obligation.

  • Free — no charge, no catch
  • 30 minutes with a senior architect
  • M365-specific, honest assessment
  • No obligation to proceed
M365 Security Specialists

Book Your
Ignite Assessment

Whether you need a full M365 hardening engagement or want to check readiness before enabling Copilot — we'll tell you exactly where you stand.

Book Ignite Assessment