Cybersecurity — Email Security
Email security services for New York businesses
Most losses start in a mailbox — a credential phish or a quiet payment redirect. We harden Microsoft 365 mail, take DMARC to enforcement, and put process around the messages that move money.
Business email compromise, without the drama
BEC is fraud, not malware. The attacker phishes a credential or registers a lookalike domain, reads invoice traffic for a few weeks, then sends a real-looking message changing the bank details on a real payment. Nothing detonates. No antivirus objects. The money simply goes to the wrong account, and it is usually unrecoverable by the time anyone compares notes.
Because the messages look legitimate, no single filter stops this. The defense is layered: authentication so your domain cannot be spoofed, tenant hardening so a compromised mailbox cannot quietly forward mail out, tuned filtering for what arrives, monitoring for the mailbox-rule fingerprints attackers leave, people who report fast, and — bluntly — a payment-change procedure that does not rely on email at all.
Email security is part of our managed cybersecurity practice and pairs directly with identity security: MFA is what makes a phished password insufficient.
What’s included
Microsoft 365 mail hardening
Anti-phishing, safe-links and attachment policies, external-sender tagging, and outbound controls across your M365 tenant — configured deliberately, not left at defaults.
Filter tuning
Detection policies tuned to your mail flow, with false positives and misses reviewed on cadence instead of accumulating.
DMARC, DKIM, and SPF to enforcement
Authentication implemented fully — not parked at monitor-only. Detailed below, because most deployments stop halfway.
Mailbox-rule and forwarding monitoring
New inbox rules, auto-forwards, and delegate changes feed the log pipeline — the most reliable early sign of a compromised mailbox.
Payment-process guidance
A verification procedure for bank-detail changes and wire requests that survives a fully compromised email thread.
Escalation path
When something does get through, a defined handoff to incident response — because minutes matter on a fraudulent wire.
DMARC, DKIM, and SPF, taken to enforcement
The three acronyms do simple work. SPF publishes which servers may send mail as your domain. DKIM cryptographically signs the mail you actually send. DMARC tells the receiving world what to do when a message fails both — and reports attempts back to you. Together they make your domain hard to impersonate, including to your own clients.
Most organizations that “have DMARC” are sitting at monitor-only, which changes nothing about delivery — spoofed mail still lands. The reason is fear: enforce too early and you block your own newsletter platform or invoicing tool. So we do the unglamorous part first: inventory every legitimate sender, fix SPF and DKIM alignment for each, watch the reports, then move to quarantine and reject in deliberate stages. Enforcement is the goal; the inventory is the work.
A side effect worth having: correctly authenticated mail is also mail that reaches your clients’ inboxes — major mail providers now require authentication from bulk senders, and unauthenticated domains increasingly land in spam.
Where email security fits
Email is where most intrusions start, which makes this the highest-leverage page in the security practice for many firms. It works as a system with its neighbors: MFA and conditional access so a phished password is not enough, awareness training so the phish that slips through gets reported in minutes, and MDR for the payload cases.
It is also a standing item on cyber-insurance questionnaires and client security reviews, which increasingly ask about email authentication and filtering by name. Firms in legal, accounting, and financial services — where email moves engagements and money — carry the most concentrated exposure.
Good fit if
Payment approvals or bank-detail changes happen over email
Your M365 tenant runs on defaults nobody has revisited
You have had a near-miss wire or a spoofed invoice
A client or insurer asked about DMARC by name
Your legitimate mail keeps landing in spam
Common questions
We have Microsoft 365's built-in filtering. Isn't that enough?
The defaults are a floor. Microsoft’s filtering is capable, but out of the box it is generic, the tenant’s anti-phishing and outbound policies are permissive, and nobody is reading what it flags. Tuning the policies, enforcing authentication, and putting the logs in front of someone is what turns a licensed feature into a control.
Will DMARC enforcement break our legitimate mail?
Done abruptly, yes — that is exactly why most deployments stall at monitor-only. We inventory every service that legitimately sends as your domain, fix alignment for each, and only then step up enforcement, watching the failure reports at every stage. Careful is the method; enforcement is still the destination.
Can you stop every phishing email?
No, and nobody can — a claim otherwise should end the meeting. The honest goal is layered: fewer phish arrive, the ones that arrive are harder to act on, a click alone is not a loss, and a report reaches someone who can contain it within minutes.
What should we do about wire and payment requests?
Adopt one rule and make it cultural: bank-detail changes and payment instructions are verified through a channel that is not the email thread — a known phone number, in person, or inside your accounting system. We help you write the procedure and train the people who approve payments, because this single control defeats the majority of BEC attempts outright.
How does this relate to security awareness training?
Directly. This page reduces what reaches the inbox and limits the damage of a click; training shortens the time between the click and the report. Controls first, people as depth — in that order, on purpose.
Make your domain hard to impersonate.
An assessment includes your current mail authentication posture — most firms are surprised by what is spoofable.