Cloudflare Vite plugin exposes secrets over the built-in dev server

QFinch assessment

Note: originally posted on H1 but closed. Cross-posting over to here in abundance of caution instead of a public issue. When utilising the Cloudflare Vite plugin in its default configuration, all files are exposed by the local dev server, including files in the root directory that contain secret information such as: - .env - .dev.vars

Potential impact

If the vite dev server is exposed on a public network, such as when a user simply uses wrangler to serve their application and doesn't publish to Cloudflare in production, an attacker may be able to acquire secrets that the user doesn't wish to be exposed. Another common scenario where this could happen is when sharing previews of an application using cloudflared. npm run dev -> share preview with cloudflared -> now all secrets are exposed to the public internet. Exposing via vite is possible via: The default configuration has no reason to expose information outside of the configured assets directory. Example: curl http://somehost/.env may expose secrets curl http://somehost/.dev.vars may expose secrets curl http://somehost/package.json may expose dependencies used by the project, potentially leading to other vulnerabilities curl http://somehost/README.md may expose internal documentation etc. Information disclosure to anyone on the same network, or if the dev server is exposed such as via cloudflared as explored here: https://github.com/cloudflare/workers-sdk/discussions/3455discussioncomment-6165773