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Finance

Microsoft 365 Exchange Online Security Hardening

A layered Microsoft 365 security framework, aligned with NIST and CIS, that cut phishing incidents by 92% in 90 days.

Client
Confidential financial services firm
Industry
Finance
Timeline
Results within 90 days
92%Fewer phishing incidentsWithin 90 days
90Days to resultsFrom rollout to measured drop
CompleteAudit trailReady for regulatory review

The challenge.

The firm relied on Exchange Online for daily communication and sensitive information. Repeated phishing attempts put accounts and data at risk.

  • Frequent phishing targeting employees
  • Limited protection against malicious and fraudulent email
  • Little visibility into mailbox access and activity
  • Risk of unauthorized access to sensitive information
  • Hard to keep complete records for compliance reviews
  • Security had to improve without disrupting operations

What we did.

Five layers, aligned with the NIST Cybersecurity Framework and CIS Controls.

Email threat protection

Phishing and malware stopped before the inbox.

Exchange Online Protection and Microsoft Defender for Office 365 strengthened defenses against phishing, spam and malicious content.

Identity and access

Only the right people get in.

Multi-factor authentication and Conditional Access policies reduced the risk of unauthorized account access.

Email authentication

Nobody can send as you.

SPF, DKIM and DMARC verify legitimate senders and prevent domain impersonation.

Mailbox audit logging

A clear record of who did what.

Detailed mailbox audit logging improved visibility into access and user activity for investigations and compliance.

Continuous monitoring

Security posture watched, not assumed.

Ongoing monitoring aligned with NIST and CIS practices identifies risks as they appear.

The outcome.

  • 92% reduction in phishing-related incidents within 90 days
  • Stronger protection against email-based threats
  • Improved security for Microsoft 365 accounts
  • Better visibility into mailbox access and activity
  • Continuous monitoring of security and compliance controls
  • Complete audit trail for regulatory review
  • Minimal disruption to employees and operations
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