Vite is a frontend tooling framework for javascript. The Vite dev server option `server.fs.deny` can be bypassed on case-insensitive file systems using case-augmented versions of filenames. Notably this affects servers hosted on Windows. This bypass is similar to CVE-2023-34092 -- with surface area reduced to hosts having case-insensitive filesystems. Since `picomatch` defaults to case-sensitive glob matching, but the file server doesn't discriminate; a blacklist bypass is possible. By requesting raw filesystem paths using augmented casing, the matcher derived from `config.server.fs.deny` fails to block access to sensitive files. This issue has been addressed in [email protected], [email protected], [email protected], and [email protected]. Users are advised to upgrade. Users unable to upgrade should restrict access to dev servers.
https://vitejs.dev/config/server-options.html#server-fs-deny
https://github.com/vitejs/vite/security/advisories/GHSA-c24v-8rfc-w8vw
https://github.com/vitejs/vite/commit/91641c4da0a011d4c5352e88fc68389d4e1289a5