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Koh Cyber
Google Workspace email security

Stop phishing before it reaches your inbox

Koh Cyber scans every inbound email in real time, quarantining phishing, BEC, and spam threats automatically — with no MX changes and no data retention.

15-day free trial • No credit card required • Setup in < 5 minutes

Trusted by security-conscious Google Workspace teams

BEC detectionPhishing quarantineSIEM integrationGDPR compliantSOC 2 in progress

Everything you need to secure your inbox

Four layers of detection. One dashboard. Zero configuration headaches.

Phishing & BEC detection

Deterministic rule-based detection catches lookalike domains, display-name spoofs, reply-to divergence, and BEC keyword patterns — no ML black boxes.

Real-time scanning

Every inbound email is scanned via Gmail push notifications within seconds of delivery. Threats are quarantined before your team sees them.

Zero data retention

We never store email body text. Only metadata and cryptographic hashes are persisted. Your confidential emails stay yours.

Threat feed & analytics

Live dashboard with severity breakdown, trend charts, and retrospective analysis. Export to your SIEM via the read-only REST API.

One-click quarantine release

Admins and end-users can release or trash quarantined messages from the dashboard or the Gmail sidebar add-on — no IT ticket required.

Google Workspace native

Connects via OAuth 2.0 to your Google Workspace domain. No MX record changes, no mail routing — installs in under 5 minutes.

How Koh works

Three steps. No MX changes required.

  1. Connect your Google Workspace

    Authorize Koh via OAuth 2.0. We request only the scopes we need: Gmail watch + label management. Takes under 5 minutes.

  2. Koh monitors every inbox

    Gmail pushes real-time notifications. Koh scans each message through four detection layers: authentication checks, reputation lookups, pattern analysis, and content rules.

  3. Threats are quarantined automatically

    High-severity messages are moved to a quarantine label. Your team is notified via Slack or email. Clean messages are delivered instantly.

Customer testimonials

Koh caught a CFO impersonation BEC attack that our previous tool completely missed. Setup took less than 10 minutes.

Head of ITSeries B SaaS company

The quarantine dashboard is incredibly clear. Our security team spends 80% less time triaging suspicious emails.

Security Engineer250-person professional services firm

As an MSP managing 30 GWS tenants, the API integration lets us feed Koh alerts directly into our SIEM.

Principal EngineerManaged Security Provider

Ready to protect your inbox?

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