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CASE STUDY

Tier-1 Bank: Microsoft 365 Security Baseline Across 80,000 Mailboxes

A tier-1 bank rolled out a hardened Microsoft 365 security baseline across 80,000 mailboxes. Phishing-related incidents dropped 76%.

May 9, 2026 · 2 min read · By admin
At a glance
76% CHANGE
Industry
BFSI
Topics
Cybersecurity · Microsoft · Microsoft 365
Published
May 2026
Headline outcome
76% Phishing-related incidents: down 76%

Measured outcomes

What this programme actually delivered.

76%

Phishing-related incidents: down 76%

84%

Sensitive-data exposure incidents: down 84%

12,000

Conditional Access blocked 12,000+ risky logins/month

The challenge

A tier-1 bank’s Microsoft 365 estate had grown organically. Security baseline was inconsistent; phishing was the most common entry vector for incidents.

What we built

Hardened baseline — Conditional Access policies, ATP/Defender for Office, sensitivity labels, retention policies, audit logging. Phased rollout with measured impact at each stage.

Outcomes

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