GHSA-rq7w-g337-39qq

### Summary

When running `nuxt dev`, Nuxt registers an unauthenticated route at `/.well-known/appspecific/com.chrome.devtools.json` that returns the absolute filesystem path of the project root and a per-project UUID persisted to `node_modules/.cache/nuxt/chrome-workspace.json`. The route is enabled by default via `experimental.chromeDevtoolsProjectSettings: true`.

The endpoint exists to let Chrome DevTools' Workspace integration map sources to the developer's local checkout. The handler is registered directly on `nitro.options.devHandlers` and does not pass through the CORS / origin wrapper that the rest of the dev pipeline uses, so it has no host / origin / `Sec-Fetch-Site` check of its own.

### Impact

Dev-server only. Production builds do not register the route.

Two values are disclosed:

- `workspace.root`: the absolute filesystem path of the project (commonly reveals the OS username and the on-disk project name). - `workspace.uuid`: a v4 UUID persisted to `node_modules/.cache/nuxt/chrome-workspace.json`, stable across dev-server restarts and re-clones.

### Threat model

The response carries no `Access-Control-Allow-Origin` header. A cross-origin `fetch()` from an arbitrary malicious page is therefore blocked by the browser's same-origin policy and cannot read the body. The two realistic recovery paths are:

1. **LAN-adjacent attacker** when the developer runs `nuxt dev --host` (or otherwise binds to a non-loopback interface). A plain `curl http://<dev-lan-ip>:3000/.well-known/appspecific/com.chrome.devtools.json` returns the JSON; no browser, no CORS. 2. **DNS rebinding** against the default loopback dev server. A page the developer visits resolves to the attacker, then re-resolves to `127.0.0.1` after the TTL; the browser believes the request is same-origin and reads the response.

### Affected versions

`nuxt@4.0.0-alpha.1` (PR #32084) through `nuxt@4.4.6`. `3.x` is not affected.

### Reproduction

```bash npx nuxt dev curl -s http://localhost:3000/.well-known/appspecific/com.chrome.devtools.json # {"workspace":{"uuid":"...","root":"/Users/<name>/..."}} ```

### Workaround

Set `experimental: { chromeDevtoolsProjectSettings: false }` in `nuxt.config.ts`. Chrome DevTools' Workspace auto-integration will stop working; the dev server is otherwise unaffected.

### Patches

Fixed in `nuxt@4.4.7` by [#35201](https://github.com/nuxt/nuxt/pull/35201) (commit [`55c75b78`](https://github.com/nuxt/nuxt/commit/55c75b78c989b8bd210837b0e5faaebbf2b87b15)). The handler is now routed through the same host / origin gate the rest of the dev server uses, so the endpoint only responds to requests that look local.