Exchange Online email security, audited end to end

Email is still the number one attack path. Siemserva checks whether your Exchange Online protections are actually turned on and tuned.

Exchange Online and Defender for Office 365 offer strong email protection, but the defaults are not the recommended settings, and policies drift. Siemserva audits your anti-phishing, anti-malware, anti-spam, and Safe Links configuration against best practice and compliance baselines.

How Siemserva makes it better

Siemserva runs standalone for full Microsoft 365 posture across configurations, logs, and CVEs, or right alongside Exchange Online.

What Exchange Online does wellWhere teams want more
Mature anti-phishing, anti-malware, and anti-spam engines.Default policies are weaker than the recommended configuration, and few teams revisit them.
Safe Links and Safe Attachments protection (with the right licensing).Hard to confirm every protection is enabled, scoped, and prioritized correctly.
Granular transport rules and mail-flow control.No native mapping of email settings to compliance controls.
Deep integration with the rest of Microsoft 365.Findings live separately from the rest of your posture.

Side by side

CapabilityExchange OnlineSiemserva
Verifies protections are enabled and tunedManualNative checks
Best-practice baseline comparisonLimitedNative
Compliance mappingNoMCSB, CISA SCuBA
Unified with identity and device postureNoYes

Comparison reflects general capabilities at time of writing and is provided for research. Vendor features change; verify current specifics with each vendor.

Your data, and a model you can build on

Every finding, and the full graph behind it, is yours. Through the Senserva SDK and the Claude MCP you get complete access to the underlying Siemserva data, so you can query it, extend it, and build your own checks, reports, automation, and integrations on top. Nothing is locked away in a vendor cloud, and the data stays with you.

Siemserva does not just record pass or fail. It models your target environment, the identities, devices, applications, policies, and how they relate, as a queryable graph. That makes the data a foundation for new work: custom analysis, threat hunting, and automation, not a static checklist you read once and set aside.

Full data access via SDK and MCPA modeled environment, not just checksBuild your own extensions

A closer look

Email is still the number one attack vector

The majority of breaches start in the inbox: phishing, business email compromise, and malicious attachments. Exchange Online Protection (EOP) is the built-in first line, with Microsoft Defender for Office 365 adding Safe Links and Safe Attachments to detonate URLs and files before users reach them. The protection is only as good as the policy: default policies are deliberately permissive, and custom anti-phishing, anti-spam, and anti-malware policies are where real tuning happens.

Email authentication: SPF, DKIM, and DMARC

Stopping spoofing of your own domain depends on three DNS-based standards. SPF lists who may send for your domain, DKIM cryptographically signs outbound mail, and DMARC tells receivers what to do when SPF or DKIM fail and where to send reports. A DMARC policy stuck at p=none, or missing DKIM, leaves the door open to impersonation. Getting all three to enforcement is one of the highest-value, lowest-cost email hardening steps.

Mailbox and transport risks that get overlooked

Beyond filtering, the configuration around mailboxes is a frequent weak spot: external auto-forwarding that quietly exfiltrates mail, overly broad mailbox delegation and full-access permissions, transport rules that bypass filtering, and legacy authentication protocols (POP, IMAP, basic auth SMTP) that cannot enforce MFA. These are the settings attackers abuse after an initial compromise to maintain access and move mail.

Compliance expectations for email

Frameworks from CIS to the CISA SCuBA Exchange Online baseline call out the same controls: enforce DMARC, disable legacy auth, block auto-forwarding, and turn on Safe Links and Safe Attachments. Treating these as a checklist mapped to the standard you answer to makes email both safer and easier to audit.

Frequently asked

Does Siemserva replace Defender for Office 365?

No. Defender enforces email protection; Siemserva verifies it is configured to best practice and maps it to compliance, alongside the rest of your tenant.

Do I need to install agents or grant broad access?

No agents and no cloud service. Siemserva reads your tenant through Microsoft's APIs and runs on Windows or Mac. You can explore the whole product first on the free Advanced Microsoft 365 Security Simulator, with no access to your environment at all.

Can I try Siemserva before I buy?

Yes. The Advanced Microsoft 365 Security Simulator and the game let you explore a full scan, the findings, the AI, and the reports for free. Scanning your own tenant uses a license key, and 501(c)(3) nonprofits get the full version free.

Does Siemserva work for MSPs and multiple tenants?

Yes. It supports multi-tenant and MSP fleets, with bulk tenant security audits and unified, client-ready reporting across many customers.

How does Siemserva use AI, and does it cost extra?

Siemserva is built for AI from the ground up and also runs fully without it. Turn it on for AI-enhanced reports and to run the product from Claude, or the AI of your choice, via our market-leading MCP. You bring your own model, so there is no AI markup, and the rich data model keeps calls and cost low.

Try the Advanced Microsoft 365 Security Simulator

See exactly what Siemserva finds on a rich, realistic simulated tenant, no access to your environment needed. Launch it right after install, or ask for a free key. Teams report cutting Microsoft 365 and Azure hardening time by up to 80 percent.

Launch the Simulator, free