AWS access key ID in the browser bundle after a Claude Code session
Identifies an IAM principal. Paired with its secret, it grants that principal’s permissions.
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.
- 1Deactivate the access key in IAM, then delete it once nothing is broken.
- 2Read CloudTrail for the period the key was public. This is the one provider where you can find out exactly what was done.
- 3Replace long-lived keys with a role, and issue presigned URLs from a server route instead of shipping credentials.
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_API_KEY;
const result = await callTheApi(key, body);After — stays on a route handler or server action
// supabase/functions/proxy/index.ts — runs on a route handler or server action
Deno.serve(async (request) => {
const key = Deno.env.get('API_KEY')!; // never sent to the browser
const result = await callTheApi(key, body);
return Response.json(result);
});
// src/components/Chat.tsx
const result = await fetch('/functions/v1/proxy', { method: 'POST' }).then((r) => r.json());How KeyDrift detects it
Matches the `AKIA` and `ASIA` prefixes. `ASIA` is a temporary STS credential and expires on its own, so it is reported one level lower. The documented example key from the AWS guides is excluded by name.
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.