Email dan DNS for Supabase

medium6 checks

Email authentication protects the brand, not the website. SPF, DMARC, DKIM, DNSSEC and CAA are cheap controls that stop spoofing and rogue certificates.

What Supabase must have

  • SPF record ending in -all with every legitimate sender listed
  • DMARC published, moving from p=none to quarantine then reject
  • DKIM signing enabled on the mail provider
  • DNSSEC signed at the registrar
  • CAA record restricting which CAs may issue certificates
  • MTA-STS and TLS-RPT for inbound mail

How to fix it

  1. 1Publish DMARC in monitoring mode first, then tighten after reviewing reports
  2. 2Add CAA for the CA you actually use, usually letsencrypt.org

Supabase context

Postgres backend platform with auth, storage and auto-generated REST APIs.

Row Level Security is mandatory — a leaked anon key plus missing RLS exposes the whole database.