Bolt.new + Supabase: the service_role default you did not choose
Fast scaffolding plus fastest-path wiring usually means one JWT in every bundle. Verify your Bolt-built app free — no signup.
Scaffolding optimizes for a working demo, and the demo works fastest when the client holds a key that ignores row-level security entirely.
This page separates the two Supabase keys your Bolt project probably ships, tells you which one matters, and walks the fix.
What actually happened
Bolt generated the Supabase client with both keys available; the queries that needed results used whichever returned rows immediately. Nothing errored on the way — that is what separates this failure from the ones your tooling catches.
- Client initialization references an env var for the service credential.
- RLS errors in preview get "fixed" by switching to the key without RLS.
- Build substitutes the literal JWT; policies exist but are moot.
- Deployment publishes the bypass to everyone.
Every step above is individually reasonable and none of them prints a warning. The value crosses into the bundle during substitution, not execution, so nothing in your runtime ever sees the moment it happened.
What someone can do with it
Identical stakes to any service_role leak:
- Every table, every operation, policies notwithstanding.
- User impersonation via admin endpoints.
Rotate first
Rotate before you touch any code. The key has been served to every visitor since the deploy that introduced it, cached by CDNs along the way, and very likely harvested by crawlers that scan served JavaScript for exactly these shapes. Dashboard → Settings → API → rotate; then point all server consumers at the new value. Removing the string from source does not un-publish it; only revocation closes the door.
A rotated key left in old deploys is still discoverable in CDN caches and archived copies. Rotation plus redeploy closes both halves; either alone leaves the door ajar.
Move the call somewhere the browser cannot read
The structural fix is always the same shape: the call moves to a context that holds the key without serving it, and the browser asks your server instead.
createClient(url, import.meta.env.VITE_SUPABASE_SERVICE_ROLE_KEY)// Edge Function holds the privileged client;
// browser uses the anon key against RLS-guarded views.Check whether yours is exposed
You can check manually right now: open the site, view source or open DevTools, and search the built JavaScript for eyJ. A hit means the string shipped; decode or prefix-check it before deciding how bad the news is.
Manual searching proves one page on one day. KeyDrift fetches the deployment the way a browser would, follows chunks named only in route manifests, reads streamed hydration payloads, and classifies what it finds — secret, or public-by-design — so an anon key never shows up dressed as an emergency.
Keep it from coming back
One more thing worth knowing before you close the tab: fixing this once does not end the story. Agents imitate whatever pattern is already in the repo, templates carry their own defaults, and the next feature request can reintroduce the same shape of code. Continuous monitoring re-scans every deploy and alerts only on change — new, regressed, resolved — so the comeback attempt is a notification instead of a quarter-end surprise.
“But RLS is enabled”
Enabled policies constrain the anon/authenticated roles. service_role carries BYPASSRLS — it is the designed exception to everything you wrote. Enabling RLS is necessary; using a bypassing key client-side negates it.
The bigger picture
Zoom out and the pattern is bigger than one repo. AI-assisted output has outgrown review capacity everywhere at once, which means thousands of teams are making the same reasonable-looking tradeoffs in the same week. Bolt.new users are not uniquely exposed — they are typically exposed. The failure mode documented above is the modal outcome of velocity without verification, not evidence of carelessness.
How KeyDrift reports this exact finding
Report anatomy matters during incidents, so it is worth reading once calmly: masked string (never the live value — it ceases to exist outside the detection engine), salted fingerprint (trackable within your workspace, useless to strangers), chunk path (your starting point for a "git log -S" hunt), disposition (secret versus public-by-design), confidence (matches below 0.5 never reach the page at all).
Manual check, step by step
The full manual drill, for readers who want zero dependence on any tool: open the deployed site in a private window; launch DevTools → Sources; use Search-all-files (Ctrl/Cmd+Shift+F) for eyJ; then repeat for the other marker families — eyJ, sk_live_, sk-proj-, AKIA, postgres, BEGIN PRIVATE KEY. Decode anything JWT-shaped before reacting, and classify public-by-design formats as expected guests rather than intruders.
Close the loop with monitoring
If you take one operational step from this page, make it this: put the URL under continuous monitoring (free tier covers one project daily). The first scan tells you whether you have a problem today; the schedule tells you whether the problem comes back next month after someone re-adds the convenient line.
Common questions
We use the new sb_secret_ format — different risk?
Same severity, newer format. See the sb_secret_ deep-dive for format specifics.
Can I detect which key a bundle uses without decoding?
KeyDrift decodes JWT payloads automatically; manually, paste the token into any JWT decoder and read role.
Run a free scan at keydrift.dev/scan — paste a URL or the bundle source itself, no account. Findings arrive masked, with the exact chunk they live in.
Related
KeyDrift is an independent product and is not affiliated with, endorsed by, or sponsored by Bolt.new. The name is referenced descriptively.