How to map your external attack surface in under 5 minutes
Most teams don't really know what their external attack surface looks like.
And that's a problem — because attackers do.
Every exposed domain, open port, forgotten API, or shadow SaaS app is an entry point. If you don't know it exists, you can't secure it.
The good news? Mapping your external attack surface doesn't have to take hours or require a security team.
With Tresal, you can get a full overview in under 5 minutes. Here's how.
Step 1: Enter your domain
Go to www.tresal.eu and enter your company domain (e.g. yourcompany.com).
Tresal will automatically begin scanning for:
- Subdomains (public, test, staging)
- Connected services and SaaS apps
- Open ports and exposed services
- Found credentials in public or private breaches
- Certificates and DNS entries
No login or setup required to preview.
Step 2: Get instant visibility
Within minutes, you'll see:
- A map of your known and unknown public-facing assets
- All kinds of subdomains (prod, non-prod, test etc.)
- Found credentials in public or private breaches and more!
You'll be surprised what turns up: legacy apps, unsecured login pages, old test environments...
Step 3: Prioritize what matters
Tresal doesn't just show you the data — it helps you act on it.
For every finding, you get:
- A plain-English description of the issue
- Why it matters from an attacker's perspective
- Suggested fixes or next steps
This means you can go from unknown risk to resolved issue fast — no security background required.
Step 4: Monitor continuously
Mapping your attack surface once is helpful. But attackers don't stop scanning — and neither should you.
With a free Tresal account, you can:
- Get notified of new exposures as they appear
- Track historical changes in your digital footprint
- Export findings and share with your team
No bloat. No noise. Just visibility.
Why it matters
Security starts with knowing what's online.
If you don't have a complete map of your external attack surface, you're flying blind. And every day, something new might pop online without anyone noticing.
Tresal helps you fix that in minutes.
No agent. No deployment. No sales call.
Just answers.
Know what's exposed. Before attackers do.
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Matthias
CPO & Cyber Security Enthusiast
CPO bridging product strategy and cybersecurity—sharing insights on secure product design, attack surface awareness, and platform risk management.
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