Stripe secret key in the browser bundle after a Claude Code session
Charge cards, issue refunds, and read every customer record on the account.
Why Claude Code does this
A CLI agent working across the repo will follow the pattern it already sees. If one component reads a key from `import.meta.env`, the next feature it writes will too — the leak spreads by imitation rather than by a single mistake.
Confirm it first
Before rotating anything, check whether the key is actually being served. Paste your deployed URL — KeyDrift downloads the same JavaScript a visitor gets and tells you what is in it.
Rotate the key
Do this before changing any code. The key has been served to browsers, cached by CDNs and very likely scraped already — removing it from the source does not un-publish it.
- 1Roll the key in the Stripe dashboard. Rolling issues a replacement and revokes the old key.
- 2Review recent charges, refunds and payouts for anything you did not initiate.
- 3Move the Stripe call into a server route. The browser only ever needs the publishable key.
Move the call to a server
The replacement key must not follow the old one into the bundle, which means the code that uses it cannot live in the browser.
Before — shipped to the browser
// src/components/Chat.tsx
// Vite substitutes the literal value here at build time.
const key = import.meta.env.VITE_STRIPE_SECRET_KEY;
const result = await new Stripe(key).checkout.sessions.create(body);After — stays on a route handler or server action
// supabase/functions/checkout/index.ts — runs on a route handler or server action
Deno.serve(async (request) => {
const key = Deno.env.get('STRIPE_SECRET_KEY')!; // never sent to the browser
const result = await new Stripe(key).checkout.sessions.create(body);
return Response.json(result);
});
// src/components/Chat.tsx
const result = await fetch('/functions/v1/checkout', { method: 'POST' }).then((r) => r.json());How KeyDrift detects it
Matches `sk_live_` and `sk_test_`, then reads the surrounding code. Clerk issues secret keys in exactly this format and nothing in the string distinguishes them, so when only Clerk is referenced nearby the finding is attributed to Clerk, when both are the finding names both, and a `sk_test_` key is reported at medium because no real money can move.
It will happen again
A CLI agent working across the repo will follow the pattern it already sees. That has not changed because you fixed this one file — the next feature request produces the same shape of code. Continuous monitoring re-scans every deploy and tells you the moment a key comes back.