Source code
Security & compliance
Stability
Cost
Email safety
Mail that reaches the inbox, and only the intended one.
Overview
Runs when the repo sends transactional or bulk mail through Resend, SendGrid, SES, Postmark, Nodemailer, or similar. lumioguard reads the send paths and the template assembly for deliverability gaps, injection points, and data that should never have left the building.
What it looks for
- Recipient or header values taken from request input without validation
- A sending domain with no SPF, DKIM, or DMARC
- Provider API keys reachable from client code
- PII or secrets rendered into message bodies or logged on send
- Unescaped template input, unthrottled sends, and bulk mail with no unsubscribe path
Why it matters
Unauthenticated sending domains land your password resets in spam, which reads to users as an outage. Unvalidated recipient and header input turns your send endpoint into someone else’s mail relay.
Rules in this check
| What it reports | Fix path |
|---|---|
| Header/recipient injection | Guide |
| Unverified sender / no SPF·DKIM·DMARC | Guide |
| API-key exposure | Guide |
| PII/secret in email or logs | Guide |
| HTML injection | Guide |
| No throttling | Guide |
| Missing unsubscribe | Guide |
How the fixes arrive
GuideChanges only you can make safely arrive as a step-by-step guide you can follow yourself or hand to your coding agent.
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