Wildcard DNS

What It Does

Detects wildcard DNS by querying two independent cryptographically random subdomains and comparing responses. Wildcard is confirmed only when both probes return matching records (preventing false positives from load balancers). Returns the wildcard record type (A, AAAA, CNAME) and target. Beyond A/AAAA/CNAME, also tests whether MX and TXT records wildcard — wildcarded MX means every subdomain receives mail (a real exfiltration / phishing risk), and wildcarded TXT can break SPF/DMARC/DKIM lookups by returning unexpected values for non-existent labels. Probes both label-depth 1 and depth 2 to distinguish an RFC 4592 single-label wildcard from a CDN-style catch-all that synthesizes records at any depth. When the wildcard is a CNAME pointing to a known takeover-prone service (GitHub Pages, Heroku, S3, Azure, Fastly, Netlify, Shopify, WordPress, Ghost, Zendesk, etc.), surfaces a `takeover_risk` flag with concrete remediation advice.

Why It's Useful

Three classes of wildcard misconfiguration matter and most tools detect only one. (1) NXDOMAIN-bypass: standard wildcard makes subdomain enumeration noisy. (2) MX/TXT wildcards: high-impact but rarely tested — every subdomain getting mail is a phishing vector. (3) Wildcard CNAME to an unclaimed third-party service: every subdomain becomes a takeover vector simultaneously. EdgeDNS catches all three in one call and gives wildcard-CNAME findings the same fingerprint set used by the dedicated subdomain-takeover endpoint.

Use Cases

Parameters

Response Fields

Code Examples

curl "https://api.edgedns.dev/v1/dns/wildcard" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d "domain=example.com"

const response = await fetch(
  'https://api.edgedns.dev/v1/dns/wildcard?domain=example.com',
  {
    headers: {
      'Authorization': 'Bearer YOUR_API_KEY'
    }
  }
);

const data = await response.json();
console.log(data);

import requests

response = requests.get(
    'https://api.edgedns.dev/v1/dns/wildcard',
    headers={'Authorization': 'Bearer YOUR_API_KEY'},
    params={
    'domain': 'example.com'
    }
)

data = response.json()
print(data)

Related Endpoints

External References

Learn more about the standards and protocols behind this endpoint.