Email security

Every message, inspected. Threats stopped before the inbox.

Tap a message to see which detection chains fired.

EMAIL INSPECTION QUEUECLOUDFLARE EMAIL SECURITYDELIVERED0(0%)QUARANTINED0(0%)BLOCKED0(0%)AGESENDER · SUBJECTVERDICT
On this page
AI summary Machine-readable context is available at /ai-index.json

Nanosek provides Cloudflare Email Security services for organizations defending against phishing, business email compromise, spoofing, impersonation, malicious links, malware attachments, and QR phishing. The service includes threat detection tuning, MX routing integration, policy design, mail platform alignment, deployment readiness, false-positive handling, DNS authentication alignment, visibility, reporting, and managed operations.

cloudflareemail securityphishing protectionbusiness email compromisebec protectionemail spoofingimpersonation defensemalicious link protection

Who this is for

Security teams and IT leaders responsible for protecting email against phishing, BEC, spoofing, and inbound malware.
Organizations deploying Cloudflare Email Security and needing expert configuration, tuning, and integration with existing mail platforms.
Enterprises that need deployment readiness planning, policy design, false-positive handling, and managed email security operations.

What Cloudflare Email Security helps protect

Phishing attacks

Targeted phishing campaigns try to steal credentials, redirect payments, or install malware. Cloudflare Email Security analyzes message content, links, sender behavior, and threat signals to identify and quarantine high-confidence phishing.

Business email compromise

BEC attacks impersonate executives, suppliers, or finance contacts to authorize transfers, change payment details, or access sensitive data. Nanosek configures detection policies that flag impersonation before messages reach inboxes.

Spoofing and sender impersonation

Attackers spoof domains, display names, and lookalike addresses to bypass basic filters. Cloudflare Email Security layers sender analysis, domain similarity checks, and authentication signals to catch spoofed messages.

Internal impersonation

Attackers who compromise or spoof internal accounts can attack other users from trusted sources. Detection policies need to handle internal message paths and trust relationships carefully.

Malicious links in email

URL-based attacks deliver phishing pages, credential harvesting sites, malware downloads, and drive-by exploits through links that look legitimate. Link inspection and rewriting improve post-delivery control.

Malware and malicious attachments

Attachments can carry ransomware, trojans, or macro-based malware. Deep file inspection and sandbox analysis help catch threats that evade basic antivirus engines.

QR phishing

QR codes embedded in email bypass link scanners and direct users to phishing pages from personal devices. Cloudflare Email Security can analyze QR code content in attachments and message bodies.

Vendor and third-party email compromise

Attacks through compromised suppliers or partner email accounts arrive from trusted senders. Nanosek helps tune policies that account for legitimate third-party sending patterns while flagging unusual behavior.

Graymail and lookalike campaigns

Mass phishing campaigns targeting multiple users can use URL variation, slight header changes, or lookalike domains to avoid batch detection. Policy rules need breadth as well as precision.

DNS authentication gaps

SPF, DKIM, and DMARC gaps allow spoofing and degrade email deliverability. Nanosek aligns email authentication with Cloudflare DNS management to close gaps before deploying enforcement.

Outbound email exposure

Outbound mail from compromised accounts or misconfigured systems can damage domain reputation and enable attackers. Policy visibility and monitoring help detect unusual outbound patterns.

False-positive risk and user friction

Aggressive filtering can quarantine legitimate email from finance, legal, suppliers, and executives. Deployment readiness and allow-list planning reduce operational disruption during rollout.

Shadow IT and unmanaged mail flows

Mail from SaaS platforms, marketing tools, and unmanaged sending infrastructure may not be authenticated or monitored. Discovery and DNS audit steps identify gaps before enforcement.

Visibility and alert fatigue

Email security generates high alert volumes. Nanosek helps prioritize signals, configure actionable dashboards, and build workflows that let security teams investigate efficiently.

Why email security needs careful deployment

Email security controls can quarantine legitimate mail from executives, finance teams, legal counsel, suppliers, and customers. Nanosek designs a staged rollout with threat review, allow-list planning, and user communication before enforcement changes are promoted.

Finance and wire transfer emailExecutive communicationsLegal and compliance mailSupplier and vendor emailCustomer-facing notificationsSaaS and marketing platformsInternal IT and monitoring alertsHR and payroll systems

Our Cloudflare Email Security approach

Phase 1

Discovery and mail flow inventory

  • Inventory email domains, mail flow architecture, MX routing, sending infrastructure, third-party senders, SaaS platforms, and current authentication status.
  • Review SPF, DKIM, DMARC, and BIMI records across all sending domains and identify gaps before enforcement begins.
Phase 2

Threat baseline and detection review

  • Analyze current threat volume, attack types, sender patterns, phishing campaigns, BEC attempts, and historical security events.
  • Review detection configuration, policy rules, quarantine thresholds, and existing allow-list or block-list entries.
Phase 3

Policy design and integration planning

  • Design detection policies for phishing, BEC, spoofing, malicious links, attachments, and QR phishing based on risk tolerance and business context.
  • Plan MX routing changes, mail platform integration, allow-list strategy, remediation workflows, and user notification approach.
Phase 4

Deployment and MX routing

  • Configure Cloudflare Email Security detection policies, quarantine rules, allow and block lists, and response actions.
  • Coordinate MX routing change with mail platform, DNS, and IT teams using a tested cutover and rollback plan.
Phase 5

Tuning and false-positive handling

  • Review quarantine queues, release legitimate email, update allow-list and exception rules, and refine detection thresholds.
  • Work with end users, IT teams, and business owners to validate that critical mail flows are unaffected by enforcement changes.
Phase 6

Monitoring and managed operations

  • Configure dashboards, alerting, reporting, and incident workflows for ongoing email security operations.
  • Provide regular threat review, policy tuning, campaign analysis, allow-list hygiene, and managed Cloudflare operations.

Architecture

Mail flow architecture: MX routing model, inbound and outbound paths, third-party senders, SaaS platforms, and failover or backup MX design.
DNS authentication alignment: SPF record design, DKIM key management, DMARC policy progression from monitoring to quarantine to reject.
Detection policy design: threat category coverage, sensitivity thresholds, quarantine vs. allow vs. reject actions, and user notification model.
Visibility and operations: quarantine workflows, dashboard design, alerting thresholds, incident response workflows, and managed tuning cadence.

Cloudflare Email Security capabilities we help operationalize

Phishing detection

Used to identify and quarantine high-confidence phishing messages based on content, links, sender signals, and threat intelligence.

BEC detection

Used to detect executive impersonation, financial fraud indicators, lookalike senders, and urgency-based social engineering patterns.

Spoofing detection

Used to analyze sender domain alignment, display name spoofing, lookalike domain detection, and header anomalies.

Malicious link inspection

Used to scan URLs in message bodies and attachments and block or rewrite links leading to phishing pages, malware, or credential harvesting sites.

Attachment scanning and sandboxing

Used to inspect file attachments for malware, macros, embedded exploits, and known and unknown threat signatures.

QR code inspection

Used to extract and analyze QR code content in attachments and message bodies to detect QR phishing payloads that bypass standard link scanners.

Vendor email compromise detection

Used to flag unusual behavior from trusted supplier or partner domains including sign-ins from new locations, atypical message content, and off-pattern sending times.

Allow lists and block lists

Used to define trusted senders, trusted domains, and explicitly blocked senders to calibrate detection sensitivity and reduce false positives.

Quarantine management

Used to hold suspected threats for review, release, or deletion while ensuring users can recover legitimate messages with low friction.

Remediation and retraction

Used to remove delivered messages from inboxes after detection or updated threat intelligence when supported by the connected mail platform.

MX routing configuration

Used to route inbound mail through Cloudflare Email Security by updating MX records with a tested cutover and rollback path.

SPF, DKIM, DMARC alignment

Used to close authentication gaps that allow spoofing and to support DMARC enforcement progression without breaking legitimate sending.

Email security dashboard

Used for operational visibility including threat volume, detection trends, quarantine rates, campaign patterns, and policy effectiveness.

Alerting and reporting

Used to notify security teams of significant threat campaigns, unusual patterns, or policy changes requiring review.

API and SIEM integration

Used to export threat events, detection data, and quarantine decisions into SIEM, SOAR, or ticketing workflows.

Cloudflare DNS integration

Used to manage MX, SPF, DKIM, and DMARC records through Cloudflare DNS for unified zone management and rapid response.

Email security protection by risk area

Executive email

Common issue

CEO fraud, wire transfer requests, impersonation of leadership

Nanosek / Cloudflare approach

BEC detection, display name spoofing rules, allow-list review, and response workflow for high-risk senders

Finance and accounts payable

Common issue

Fraudulent invoice requests, payment redirection, supplier impersonation

Nanosek / Cloudflare approach

BEC and spoofing detection, vendor email analysis, DMARC alignment for outbound domains

HR and payroll

Common issue

Direct deposit fraud, employee data phishing, W-2 and tax form attacks

Nanosek / Cloudflare approach

Phishing detection, quarantine for high-risk patterns, employee notification workflows

IT and security teams

Common issue

Credential phishing, token theft, account takeover enabling lateral movement

Nanosek / Cloudflare approach

Phishing and malicious link detection, aggressive quarantine for credential harvesting indicators

Legal and compliance

Common issue

Document phishing, contract fraud, data theft via malicious attachments

Nanosek / Cloudflare approach

Attachment scanning, malicious link inspection, document-type-specific detection rules

Customer service

Common issue

Phishing using customer impersonation, BEC to redirect payments

Nanosek / Cloudflare approach

Spoofing detection, allow-list calibration to preserve customer email, quarantine review workflows

Sales and account management

Common issue

Supplier compromise, fake RFP emails, partner impersonation

Nanosek / Cloudflare approach

Vendor compromise detection, lookalike domain detection, BEC policy tuning for sales flows

Shared inboxes and service accounts

Common issue

Unmonitored attack surface, phishing reaching internal workflows directly

Nanosek / Cloudflare approach

Coverage extension to service accounts, quarantine notification configuration, allow-list review

Third-party and SaaS notifications

Common issue

Phishing impersonating SaaS platforms, misclassified notifications

Nanosek / Cloudflare approach

Allow-list planning for trusted SaaS senders, authentication alignment, false-positive review

Outbound email

Common issue

Domain reputation damage, outbound phishing from compromised accounts

Nanosek / Cloudflare approach

Outbound visibility, DMARC policy enforcement, anomaly detection for unusual sending patterns

Deployment steps

  1. 01 Inventory email domains, sending infrastructure, third-party senders, SaaS platforms, and current authentication status.
  2. 02 Review SPF, DKIM, and DMARC records and align DNS authentication before enforcement begins.
  3. 03 Design detection policies for phishing, BEC, spoofing, attachments, malicious links, and QR phishing based on risk and business context.
  4. 04 Configure Cloudflare Email Security policies, quarantine rules, allow and block lists, and coordinate MX routing change with a tested rollback plan.
  5. 05 Review quarantine queues, release legitimate email, update exceptions, and tune detection thresholds with business owner approval.
  6. 06 Configure dashboards, alerting, reporting, and incident workflows for managed operations and ongoing policy hygiene.

Risks and mitigations

Risk

Quarantining legitimate business email.

Mitigation

Build allow-list from known senders before MX cutover, review quarantine daily in the first two weeks, and maintain a fast release workflow for end users.

Risk

Disrupting inbound mail during MX change.

Mitigation

Plan the routing change with a tested rollback, reduce TTL ahead of time, validate delivery on a test domain first, and monitor error queues actively.

Risk

Breaking SaaS or transactional notifications.

Mitigation

Identify SaaS sending domains during discovery, add to allow-list before deployment, and validate delivery for critical notifications during cutover.

Risk

DMARC enforcement breaking legitimate sending.

Mitigation

Start at p=none, monitor reports for unknown senders, authorize sending sources, and only progress to quarantine or reject after full sender coverage is confirmed.

Risk

Missed threats during policy tuning.

Mitigation

Use conservative quarantine settings during the initial period rather than rely on log-only mode for high-risk categories like BEC and executive impersonation.

Risk

Alert fatigue from high detection volume.

Mitigation

Configure tiered alerting by threat confidence and category, and build a triage workflow that separates high-priority incidents from routine quarantine review.

Risk

Attackers adapting to detection.

Mitigation

Use layered detection with behavioral signals, not just pattern matching. Review campaign trends and update detection policies as attacker TTPs evolve.

Risk

Shadow sending infrastructure not covered.

Mitigation

Audit DMARC reports and DNS records for unknown senders, and inventory SaaS and marketing platforms before closing authentication gaps.

Risk

Vendor compromise arriving from trusted senders.

Mitigation

Enable vendor email compromise detection and configure alerts for anomalous behavior from known partner domains.

Risk

Governance and allow-list sprawl over time.

Mitigation

Review allow-list and exception entries quarterly, enforce owner and expiry documentation, and remove stale entries to reduce detection surface.

Deployment readiness checklist

  • All email domains and subdomains inventoried
  • MX routing architecture documented
  • Third-party senders and SaaS platforms identified
  • SPF records reviewed for all sending domains
  • DKIM signing configured and validated
  • DMARC policy reviewed (p=none, quarantine, or reject)
  • Allow-list candidates identified from business workflows
  • Finance, executive, and legal mail flows mapped
  • Current quarantine workflows and review process documented
  • Backup MX or failover routing planned
  • Cloudflare Email Security routing tested in staging or partial-flow mode
  • Detection policies reviewed and thresholds set for initial rollout
  • User notification and quarantine release process agreed
  • IT and security escalation contacts confirmed
  • Rollback plan for MX routing change prepared
  • Logpush or API integration configured for SIEM workflows
  • Dashboard and alerting configuration reviewed
  • Business stakeholders briefed on enforcement changes

Deliverables

  • Email domain and mail flow inventory
  • DNS authentication audit report (SPF, DKIM, DMARC)
  • Threat baseline and detection gap review
  • Allow-list and exception strategy
  • Email security policy design
  • MX routing change plan with rollback steps
  • Cloudflare Email Security configuration
  • DNS authentication alignment and fixes
  • Quarantine workflow and user release process
  • Tuning report and false-positive resolution log
  • Email security dashboard and alerting setup
  • Incident response workflow for email threats
  • Managed operations handover and tuning backlog

When Nanosek should help

You are deploying Cloudflare Email Security and need expert configuration and integration support.
You are experiencing phishing, BEC, or spoofing attacks that are reaching user inboxes.
Your DNS authentication is incomplete or DMARC is still in monitoring mode.
You need allow-list planning and false-positive handling before enforcement begins.
Your organization has high-risk mail flows in finance, legal, HR, or executive communications.
You have connected Cloudflare Email Security but need ongoing tuning and managed operations.
Your quarantine review and user notification process needs improvement.
You need SIEM or SOAR integration for email threat events.

Frequently asked questions

What is Cloudflare Email Security?
Cloudflare Email Security is a cloud-based email protection service that analyzes inbound email for phishing, business email compromise, spoofing, malicious links, malware attachments, and QR phishing. It routes inbound mail through Cloudflare for inspection before delivery to the connected mail platform.
Does Cloudflare Email Security replace our existing mail platform?
No. Cloudflare Email Security works alongside existing mail platforms such as Microsoft 365 or Google Workspace. It inspects inbound mail before delivery using an MX routing change, and optionally integrates with the mail platform API for remediation workflows.
How do we handle false positives?
Nanosek builds an allow-list from known business senders before deployment, monitors quarantine closely after MX cutover, maintains a fast release workflow for end users, and tunes detection thresholds based on the first weeks of production data.
Can Cloudflare Email Security protect against BEC if the attacker uses a legitimate account?
Cloudflare Email Security includes vendor email compromise detection that identifies unusual behavior from known sender domains, including anomalous sending patterns, new login locations, and atypical message content that may indicate account compromise.
Do we need to change our DNS records to deploy Cloudflare Email Security?
Yes. Inbound protection requires an MX record change to route mail through Cloudflare. Nanosek plans this with a tested cutover, reduced TTL preparation, rollback steps, and validation before moving full production traffic.
How does DMARC relate to Cloudflare Email Security?
DMARC authenticates that email claiming to be from your domain was actually sent by authorized sources. Nanosek aligns SPF, DKIM, and DMARC before enforcement so Cloudflare Email Security has reliable authentication signals and outbound spoofing is reduced.
Can Cloudflare Email Security detect QR phishing?
Yes. Cloudflare Email Security can inspect QR codes embedded in images and attachments to extract and analyze the encoded URL, allowing detection of QR phishing campaigns that embed phishing links in ways that bypass text-based link scanners.
What happens if the Cloudflare Email Security service is unavailable?
Nanosek designs a backup MX routing plan so inbound mail can be delivered directly to the mail platform if Cloudflare Email Security is unavailable. This reduces the risk of mail loss but removes inline threat inspection during that period.
Can Nanosek provide ongoing managed email security operations?
Yes. Nanosek can provide managed Cloudflare Email Security operations including policy tuning, allow-list hygiene, threat campaign review, false-positive handling, dashboard monitoring, alerting, and regular reporting.

Strengthen email security with Cloudflare

Nanosek helps you deploy Cloudflare Email Security with the right policy design, DNS authentication alignment, allow-list planning, and managed operations to defend against phishing, BEC, and impersonation without disrupting business email.

Ready to talk?

Deliver Cloudflare without surprises.

Whether you're migrating, hardening, or operating Cloudflare — Nanosek brings authorized MSP & ASDP delivery, rollback-ready cutovers, and managed operations after launch.