Find every subdomain in your attack surface
SeguriScan automatically discovers all subdomains associated with your domains — including forgotten staging servers, old marketing sites, and shadow IT — and monitors for changes weekly.
No credit card. 14-day free trial.
You can't protect subdomains you don't know about
The average organization has 40% more subdomains than they realize
Forgotten subdomains with expired SSL or outdated software are the #1 target for subdomain takeover attacks
A single unmonitored staging server can expose customer data, API keys, or internal tools
SeguriScan maps your entire subdomain footprint — and keeps watching for new ones.
Complete subdomain intelligence
All your subdomains
Passive and active discovery finds subdomains you forgot existed — staging, dev, legacy, third-party.
DNS records & WHOIS
Full DNS resolution (A, AAAA, MX, NS, TXT, CNAME) plus domain registration and expiration data.
Technologies & services
Know what software runs on each subdomain — CMS, frameworks, server software, open ports.
SSL certificate status
Spot expired, misconfigured, or missing certificates across all your subdomains before browsers warn your visitors.
Subdomain discovery in 3 steps
Add your root domains
Enter your primary domains. SeguriScan discovers all associated subdomains automatically.
Automated weekly scans
Every week, new subdomains are detected and existing ones are re-checked for changes.
Dashboard + alerts
See your complete subdomain inventory. Get notified when new subdomains appear or existing ones change.
Track every change to your digital footprint
SeguriScan monitors your subdomains with weekly automated scans — every new asset, every disappeared server is logged with DNS records and timestamps so nothing slips through unnoticed.
Subdomain discovery is one part of your attack surface
Finding subdomains is the first step. SeguriScan then scans each one for open ports, web vulnerabilities, SSL issues, and leaked credentials — giving you a complete security picture of every asset you own.
Monitor your attack surface from €79/month
Starter €79 ( assets) — Business €199 ( assets) — Enterprise ( assets). Annual billing: save 20%.
Frequently asked questions
What is subdomain discovery?
Subdomain discovery is the process of finding all subdomains (like staging.example.com, api.example.com) associated with your root domain. Organizations often have more subdomains than they realize — including forgotten test servers, old marketing sites, and third-party services. Each undiscovered subdomain is a potential blind spot in your security.
How does SeguriScan find subdomains?
Using multiple discovery techniques — passive intelligence sources, DNS analysis, and certificate transparency logs — SeguriScan finds subdomains that manual methods miss.
How often are subdomains re-scanned?
Weekly. New subdomains, removed subdomains, and infrastructure changes are tracked automatically.
What should I do when unknown subdomains are found?
Review each one: is it still needed? Is the software updated? Is SSL valid? Decommission what you don't need, secure what you keep.
Find the subdomains you didn't know you had
Add your domain. Get a complete subdomain inventory within 24 hours. Free trial, no credit card.
IE Venture Day 2025 Finalist · 15+ security scanners · 14-day free trial