Microsoft 365 Audit

Microsoft 365 Security Audit for Accounting Firms

Most accounting-firm breaches begin with identity, email, unsafe sharing, or weak administrative controls. OC Security Audit reviews Microsoft 365 and Entra ID settings that protect taxpayer data, client files, payroll records, and executive communications.

CISO-Led25+ Years ExperienceIRS WISPFTC SafeguardsMicrosoft 365 Security

High-Value Target

Why Microsoft 365 Needs Accounting-Specific Review

CPA firms often depend on Outlook, SharePoint, OneDrive, Teams, and cloud document workflows to exchange tax organizers, W-2s, 1099s, bank information, payroll records, and client financial statements. Default settings are rarely enough for this level of sensitivity.

A Microsoft 365 security audit validates the controls that reduce account takeover, mailbox forwarding, unsafe external sharing, stale admin access, weak logging, and unmanaged device access.

Audit Scope

What OC Security Audit Reviews

MFA And Conditional Access

MFA coverage, break-glass accounts, trusted locations, risky sign-in handling, device requirements, and legacy authentication exposure.

Email Security

Anti-phishing, impersonation protection, mailbox forwarding, transport rules, quarantine policies, SPF/DKIM/DMARC alignment, and user reporting.

SharePoint And OneDrive

External sharing, anonymous links, guest access, sensitive file exposure, retention, versioning, and auditability of client documents.

Admin Roles

Global admins, privileged role sprawl, service accounts, stale accounts, emergency access, and role assignment evidence.

Logging And Alerts

Unified audit log, mailbox audit, sign-in logs, risky user alerts, Defender signals, and practical monitoring workflows.

Endpoint And Device Access

Device compliance, mobile access, unmanaged browser downloads, local encryption, and access from personal or seasonal worker devices.

Related Reviews

When Microsoft 365 Connects To Broader Risk

Microsoft 365 findings often connect to network vulnerability assessment, firewall and VPN review, IRS WISP readiness, and cyber insurance evidence.

For deeper platform review, see OC Security Audit’s Microsoft Office 365 Full Audit.

Evidence Output

Practical Deliverables For Firm Leadership And IT

Configuration Findings

A clear list of risky settings, affected users, administrative gaps, and recommended changes.

Priority Fix Plan

A sequenced plan for MFA, Conditional Access, sharing controls, email protection, logging, and admin cleanup.

Compliance Support

Evidence points that support WISP, FTC Safeguards, cyber insurance, and client security questionnaire responses.

Ali Hassani, CISO

Experienced Cybersecurity Guidance For Accounting Firms

Created by Ali Hassani, CISO, with 25+ years of IT, cybersecurity, compliance, Microsoft infrastructure, network security, firewall, cloud, and IT operations experience. Ali’s background includes CISSP, CCISO, CCNP, CCNA, MCSE, MCSA Security, MCITP, MCP, and MCTS credentials.

For accounting firms, the focus is practical: protect taxpayer data, reduce email and ransomware exposure, document evidence, and help leadership understand which security fixes matter first.

From Findings To Implementation

Turn Security Findings Into Practical IT Work

OC Security Audit can identify the accounting-firm security gaps, evidence needs, and compliance risks. When the next step is implementation, IT Perfection can help with managed IT, Microsoft 365 support, endpoint operations, backup and disaster recovery, server work, and network infrastructure support for the same business environment.

CPA And Tax Firm Security Pathways

Continue The Accounting Firm Security Review

Accounting-firm security is strongest when the professional audit, IRS WISP documentation, FTC Safeguards expectations, Microsoft 365 controls, ransomware readiness, incident response, firewall, vulnerability, and backup evidence are reviewed together. These connected pages help your firm move from broad risk visibility into the exact controls that need attention.

FAQ

Questions Accounting Firms Ask

Can this review find mailbox forwarding rules?

Yes. Mailbox forwarding, suspicious inbox rules, transport rules, and external forwarding policies are core checks because they are common in business email compromise.

Does this include SharePoint and OneDrive sharing?

Yes. External sharing, anonymous links, guest access, sensitive document exposure, retention, and auditability should be reviewed for accounting firms.

Can IT Perfection help implement Microsoft 365 fixes?

When implementation support is needed after the audit, IT Perfection can assist with Microsoft 365 managed services and ongoing operational support.

Is this only for large firms?

No. Small and mid-sized accounting firms often have significant Microsoft 365 exposure because they rely heavily on email and cloud file sharing without dedicated security staff.

Next Step

Review The Controls Before A Client, Insurer, Or Incident Forces The Issue

OC Security Audit can help your accounting firm understand the most important gaps, document what needs attention, and plan remediation in a practical order.