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Email Spoofability Score

pro
GET/v1/security/spoofability

Computes a 0–100 email spoofability score by combining SPF, DMARC, and DKIM analysis with interaction multipliers that model real-world attacker risk. Unlike a weighted average, this endpoint applies compounding penalties when weak authentication policies interact — for example, DMARC p=none combined with SPF ~all more than doubles the spoofability risk of either alone.

What It Does

Runs SPF, DMARC, and DKIM analysis in parallel, then computes per-protocol protection sub-scores (SPF 30%, DMARC 45%, DKIM 25% base weights). Applies conditional interaction multipliers: DMARC p=none with permissive SPF (~all/+all) adds +30% spoofability; missing DKIM with permissive DMARC adds +20%; SPF with >10 lookups (PermError) disables SPF contribution entirely. Returns a classification (locked_down / moderate / vulnerable / open) with the contributing factors broken out, so remediation work can target the highest-impact gap.

Why It's Useful

A flat average hides the non-linear way email authentication actually fails. Real-world bypass relies on specific interactions — e.g., Gmail's ARC-aware evaluation treats a missing DKIM differently from a failing one. This endpoint surfaces those interaction risks in a single number that's comparable across your portfolio while still being drill-downable for remediation.

Use Cases

Email Security Lead

Portfolio-Wide Deliverability Risk

Score all owned domains monthly and prioritize the lowest-scoring ones for hardening ahead of Google/Yahoo bulk-sender enforcement.

Single number that's comparable across domains and trackable over time.

IT Integration Team

M&A Email Risk Assessment

Evaluate acquired brands' spoofability to plan authentication uplift during integration.

Factor email-auth debt into acquisition risk models with a quantified score.

CISO

Executive Risk Reporting

Report portfolio email-spoofability trend to the board without surfacing raw SPF/DMARC/DKIM details.

Single, stable, defensible metric for executive risk dashboards.

Parameters

NameTypeRequiredDescription
domainstringRequiredThe domain to scoreExample: example.com

Response Fields

FieldTypeDescription
domainstringThe queried domain
spoofabilitynumberSpoofability score 0–100 (higher = more spoofable)
classificationstringlocked_down | moderate | vulnerable | open
sub_scoresobjectPer-protocol protection scores (spf, dmarc, dkim) 0–100
interactionsarrayActive interaction multipliers with descriptions and impact
top_gapobjectSingle highest-impact gap to address for the biggest score improvement
findingsarrayPer-protocol findings with severity
recommendationsarrayPrioritized remediation steps
dns_errorsarrayNon-empty when any of SPF / DMARC / DKIM analysis hit a DNS infrastructure error (e.g., SERVFAIL, timeout). The score may be incomplete.
score_degradedbooleanTrue when the score is based on partial data — retry before acting on it.

Code Examples

cURL
curl "https://api.edgedns.dev/v1/security/spoofability" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d "domain=example.com"
JavaScript
const response = await fetch(
  'https://api.edgedns.dev/v1/security/spoofability?domain=example.com',
  {
    headers: {
      'Authorization': 'Bearer YOUR_API_KEY'
    }
  }
);

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

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

data = response.json()
print(data)

Read the full Email Spoofability Score guide

Why it matters, real-world use cases, parameters, response fields, and how to call it from Claude, ChatGPT, or Gemini via MCP.

Read the guide →

Related Endpoints

External References

Learn more about the standards and protocols behind this endpoint.

Try This Endpoint

Test the Email Spoofability Score endpoint live in the playground.