Lock down Microsoft 365 the way attackers wish you would not.
Microsoft 365 is the most attacked platform in modern business. Default settings are designed for productivity, not for security, and attackers know exactly which gaps to exploit. Armour Cybersecurity hardens your tenant across Exchange, Teams, SharePoint, OneDrive, identity, and admin governance, turning a productivity platform into a defensible one.
Tenant-wide hardening, baseline to baseline.
M365 Security Optimization is a structured engagement that takes your Microsoft 365 tenant from default configuration to a hardened, monitored, audit-ready state. We start with your current Microsoft Secure Score baseline, identify the gaps attackers actually exploit, implement controls across every M365 surface, and finish with a measurable post-hardening baseline that demonstrates the improvement.
The work covers everything that matters: advanced threat protection for email, multi-factor authentication enforced across users and admins, conditional access policies tuned to your business, data loss prevention across SharePoint and OneDrive, Teams governance, sensitivity labels, audit logging, and the admin account discipline that prevents privileged compromise. Each control is documented, configured, and validated so you can defend it to auditors and reproduce it across future tenants.
Armour Cybersecurity has hardened M365 environments for organizations across regulated industries worldwide. Our methodology is aligned to Microsoft Security Benchmarks, NIST CSF, ISO 27001, SOC 2, and CIS Controls so a single hardening engagement produces evidence that satisfies multiple compliance obligations.
Why default M365 configuration is not security.
Microsoft 365 ships configured for productivity. The defaults are intentionally permissive so the platform works out of the box, which is exactly why attackers prefer environments where no hardening has been done.
Without M365 hardening
- Multi-factor authentication missing or inconsistently enforced across users and admins.
- External sharing in SharePoint and OneDrive set to defaults that leak documents to anyone with a link.
- Auto-forwarding rules that let attackers exfiltrate email silently after account compromise.
- Teams guest access permissive enough that external parties can reach internal channels.
- Audit logging turned off or never reviewed when something goes wrong.
- Admin accounts shared with day-to-day user identities, expanding the attack surface.
- DKIM, SPF, and DMARC misconfigured so phishing attacks impersonate your domain easily.
With Armour Cybersecurity M365 Optimization
- MFA enforced across every user and admin, with conditional access tuned to your business.
- External sharing locked down to authorized partners with documented exception handling.
- Mail flow rules that block auto-forwarding to external addresses by default.
- Teams governance with naming policies, guest restrictions, and meeting security configured.
- Audit logging enabled, retention configured, and alerts wired to your response process.
- Dedicated admin accounts separated from daily-use identities, with privileged access controls.
- Email authentication (DKIM, SPF, DMARC) configured correctly so impersonation gets rejected.
Hardening across every Microsoft 365 surface.
Engage individual services or a coordinated full-tenant hardening program. Every service is delivered against the same standardized methodology so deliverables compose cleanly into a unified M365 security posture.
Current-State Security Assessment
Microsoft Secure Score baseline, tenant configuration review, license utilization analysis, and identification of gaps across every M365 surface. The starting point for every engagement.
Exchange Online Hardening
Advanced threat protection for email, anti-phishing and anti-spoofing policies, mail flow rules, external domain controls, and the email authentication configuration (DKIM, SPF, DMARC) that prevents domain impersonation.
SharePoint & OneDrive Security
Data loss prevention policies, sensitivity labels, external sharing restrictions, guest access controls, and the document protection configuration that keeps confidential content from walking out the door.
Teams Security Configuration
Messaging retention policies, external guest access restrictions, team governance and naming policies, meeting security settings, and the channel controls that keep collaboration private.
Identity & Access Hardening
MFA enforcement across users and admins, conditional access policies, sign-in risk policies, privileged access management, and the identity discipline that blocks the most common compromise paths.
Data Loss Prevention
DLP policies tuned to your business and regulatory obligations, sensitivity classification, automated labeling, and the encryption and rights management that protect data after it leaves the tenant.
Audit Logging & Monitoring
Audit log enablement, alert configuration, security notification setup, and integration with your incident response process so high-impact events surface immediately rather than after the damage is done.
Admin Governance
Dedicated admin accounts separated from daily-use identities, role-based access aligned to least privilege, admin activity auditing, and the privileged access controls that limit blast radius from a compromised admin.
Admin & User Training
Hands-on training for administrators covering platform management and policy enforcement, plus user-facing security awareness covering phishing, safe sharing, and incident reporting.
Built for organizations serious about Microsoft 365 security.
Companies running M365 at default settings
Organizations that deployed Microsoft 365 quickly and never hardened the tenant. The most common scenario we see, and where the largest improvement is available in the shortest time.
Compliance-driven hardening
Companies pursuing SOC 2, ISO 27001, HIPAA, PCI DSS, or CMMC certification that need M365 controls aligned to framework requirements with documented evidence for the audit.
Post-incident response
Organizations that experienced phishing-driven account compromise, business email compromise, or data exfiltration through M365 and need structured remediation across the tenant.
Mergers, acquisitions, and tenant migrations
Companies consolidating multiple M365 tenants, migrating from another platform, or onboarding an acquired business and needing consistent hardening applied across the resulting environment.
A six-phase engagement built on disciplined consulting practice.
Every Armour Cybersecurity M365 hardening engagement follows the same standardized phases. The discipline is what produces measurable improvement and audit-ready documentation.
Current-State Assessment
Document tenant configuration and settings, capture the Microsoft Secure Score baseline, review enabled security features and gaps, assess user access and external sharing, and evaluate current threat protection effectiveness.
Exchange Online Hardening
Enable advanced threat protection for email, configure mail flow rules and filtering, implement anti-phishing policies, configure external email domain controls, and validate DKIM, SPF, and DMARC for every accepted domain.
SharePoint, OneDrive & Teams Security
Implement DLP policies for document protection, configure external sharing restrictions, enable data classification and labeling, restrict guest access, configure Teams retention and meeting security, and apply governance and naming policies.
Identity & Access Hardening
Enforce MFA for all users, configure conditional access policies, implement sign-in risk policies, configure privileged access management for admins, and separate admin accounts from daily-use identities.
Monitoring & Incident Response
Enable audit logging and alerting, configure security alerts and notifications, establish monitoring procedures, and document M365-specific incident response procedures wired into your existing response process.
Validation & Post-Hardening Baseline
Capture the post-hardening Microsoft Secure Score, validate every implemented control, deliver before-and-after metrics, and hand off the documented configuration and runbooks for ongoing operation by your team.
Outputs your administrators and auditors can actually use.
Every deliverable is structured for direct use by your IT and security teams, your administrators, and your external auditors when applicable.
M365 Security Assessment Report
Current security posture across the tenant with Microsoft Secure Score baseline, prioritized gaps, and recommended remediation sequence.
Security Configuration Guide
Documented hardening implementation covering every control applied across Exchange, Teams, SharePoint, OneDrive, and identity.
DLP Policy Documentation
Data loss prevention rules, classification logic, sensitivity labels, and the business rationale behind every policy applied.
Conditional Access Rulebook
Documented conditional access policies, sign-in risk responses, exception handling procedures, and the access control architecture for the tenant.
Email Authentication Configuration
DKIM, SPF, and DMARC configuration for every accepted domain with the DNS records, selector setup, and policy progression documented.
Admin Governance Documentation
Dedicated admin account structure, role assignments, privileged access controls, and audit procedures aligned to least privilege.
Training Materials
Admin training covering platform management and policy enforcement, plus user-facing awareness materials covering phishing, safe sharing, and incident reporting.
Post-Hardening Secure Score Report
Before-and-after Microsoft Secure Score with documented improvement, control-by-control validation, and residual risk callouts for leadership consumption.
Compliance Mapping
Documented mapping of M365 controls to NIST CSF, ISO 27001, SOC 2, HIPAA, PCI DSS, and CIS Controls requirements for direct use during audits.
The numbers behind the work.
Founded by military intelligence veterans with senior advisors from PwC, KPMG, Deloitte, EY, and Mandiant. The track record reflects the discipline.
Clients Served
Organizations across finance, healthcare, technology, energy, legal, and government trust Armour Cybersecurity to protect what matters.
Client Retention Rate
Long-term engagements built on consistent quality, predictable delivery, and consulting relationships that compound in value over time.
Industries · Worldwide Reach
Cross-sector experience spanning every major regulated industry, with operations supporting clients across North America, Latin America, and beyond.
Cybersecurity Technology Solutions
A vetted catalogue of technology partnerships and proprietary methods deployed in support of every engagement.
Ready to turn Microsoft 365 from a productivity platform into a defensible one?
Schedule a no-obligation M365 security scoping conversation with our cloud security team.
Schedule an M365 Security AssessmentM365 security questions, answered directly.
What is M365 Security Optimization and how is it different from buying a license upgrade?
Will hardening break our users' productivity?
How is improvement measured?
Do you cover Microsoft Defender for Office 365?
How long does a typical M365 hardening engagement take?
Will this satisfy our SOC 2 or ISO 27001 audit requirements?
Can you handle multi-tenant environments and post-acquisition consolidation?
Schedule your M365 security scoping conversation.
Tell us about your tenant and what is driving the conversation. We will respond within one business day with next steps.
Speak with our cloud security team
Toronto, ON