Anyone can sign up with an email address they do not own
Your Supabase project allows public signups while email confirmation is turned off, so an account is active the moment it is created — no link clicked, no proof the address belongs to the person registering.
Why it matters
Your Supabase project allows public signups while email confirmation is turned off, so an account is active the moment it is created — no link clicked, no proof the address belongs to the person registering. Someone can register using a colleague's or customer's email and receive whatever that address is trusted for: team invitations, domain-based access, or a pre-existing invite. It also leaves you unable to distinguish real users from bulk-registered ones. This setting is usually switched off to make local development quicker and then carried into production by accident.
How ShipReady detects it
Tests whether a Supabase project is readable by anyone. The project URL and anon key are read from the page's own JavaScript — both are published there by design. The anon key is then used exactly as a browser would use it, against common table names, and a table is reported only when it returns actual rows. Returning an empty array is not a finding: that is what correctly configured RLS looks like. Observed rows are, because they prove the data is readable by whoever holds a key that is already public. The probe sequence is memoised on the discovered project, so a project referenced by ten pages is tested once rather than ten times.
Detection is deterministic. ShipReady reports this only when it observes the condition directly, and prefers to miss a real problem over inventing one. Rule version 1.2.0.
How to fix it
This is the prompt ShipReady puts in your report — written to be pasted straight into Cursor, Claude Code, or whichever assistant built the app.
Your Supabase project has open signups with email confirmation turned off, so anyone can register an account using an email address they do not control. In the Supabase dashboard go to Authentication -> Providers -> Email and enable "Confirm email". If you disabled it to make local development easier, re-enable it for the production project specifically. After enabling it, audit existing accounts for addresses that were never verified, and make sure any logic that trusts an email address (team invitations, domain-based access, password reset) checks email_confirmed_at rather than assuming the address is genuine.
Frequently asked questions
- What does "Anyone can sign up with an email address they do not own" mean?
- Your Supabase project allows public signups while email confirmation is turned off, so an account is active the moment it is created — no link clicked, no proof the address belongs to the person registering.
- How serious is it?
- ShipReady rates this high. Fix before launch. A real weakness that an attacker can act on.
- How do I fix it?
- Paste the fix prompt on this page into Cursor, Claude Code or your AI editor. It is the same prompt ShipReady puts in your report.
- Can I check my own site?
- Yes — ShipReady scans up to ten pages of any public site for free and reports this alongside every other check.
Related checks
Does your site have this?
ShipReady checks this and 73 other things across up to ten pages of your site. Free, no signup.
Scan my site