Threat Intelligence Database

### Summary The contents of files that are specified by [`server.fs.deny`](https://vite.dev/config/server-options#server-fs-deny) can be returned to the browser 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)) - the sensitive file exists in the allowed directories specified by [`server.fs.allow`](https://vite.dev/config/server-options#server-fs-allow) - either of: - the sensitive file exists in an NTFS volume - the dev server is running on Windows and the sensitive file exists in a volume that 8.3 short name generation is enabled (it is enabled by default on system volumes) ### Details Vite’s dev server denies direct access to sensitive files through `server.fs.deny`, including entries such as `.env`, `.env.*`, and `*.{crt,pem}`. However, on Windows, the deny logic does not correctly normalize NTFS ADS path forms before access checks are applied. Because of this, requests such as `/.env::$DATA?raw` are treated as allowed paths, while Windows resolves them to the original file's default data stream. Similar to that, Windows allows accessing a file using a different name with the 8.3 short name compatibility feature. Vite did not reject accessing files via them. ### PoC ```bash $ npm create vite@latest $ cd vite-project/ $ npm install $ npm run dev ``` Access via browser at `http://localhost:5173/.env::$DATA?raw` <img width="388" height="129" alt="deecc1315123883cfd0f9c26a002845a" src="https://github.com/user-attachments/assets/895c6012-4e2e-4a35-babb-69bbf3ee7170" /> Example expected result: - `/.env::$DATA?raw` returns the contents of `.env` - `/tls.pem::$DATA?raw` returns the contents of `tls.pem`

### Summary Any files ending with `.map` even out side the project can be returned to the browser. ### 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)) - have a sensitive content in files ending with `.map` and the path is predictable ### Details In Vite v7.3.1, the dev server’s handling of `.map` requests for optimized dependencies resolves file paths and calls `readFile` without restricting `../` segments in the URL. As a result, it is possible to bypass the [`server.fs.strict`](https://vite.dev/config/server-options#server-fs-strict) allow list and retrieve `.map` files located outside the project root, provided they can be parsed as valid source map JSON. ### PoC 1. Create a minimal PoC sourcemap outside the project root ```bash cat > /tmp/poc.map <<'EOF' {"version":3,"file":"x.js","sources":[],"names":[],"mappings":""} EOF ``` 2. Start the Vite dev server (example) ```bash pnpm -C playground/fs-serve dev --host 127.0.0.1 --port 18080 ``` 3. Confirm that direct `/@fs` access is blocked by `strict` (returns 403) <img width="4004" height="1038" alt="image" src="https://github.com/user-attachments/assets/15a859a8-1dc6-4105-8d58-80527c0dd9ab" /> 4. Inject `../` segments under the optimized deps `.map` URL prefix to reach `/tmp/poc.map` <img width="2790" height="846" alt="image" src="https://github.com/user-attachments/assets/5d02957d-2e6a-4c45-9819-3f024e0e81f2" />

### Summary The contents of files that are specified by [`server.fs.deny`](https://vite.dev/config/server-options#server-fs-deny) can be returned to the browser. ### 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)) - the sensitive file exists in the allowed directories specified by [`server.fs.allow`](https://vite.dev/config/server-options#server-fs-allow) - the sensitive file is denied with a pattern that matches a file by [`server.fs.deny`](https://vite.dev/config/server-options#server-fs-deny) ### Details On the Vite dev server, files that should be blocked by `server.fs.deny` (e.g., `.env`, `*.crt`) can be retrieved with HTTP 200 responses when query parameters such as `?raw`, `?import&raw`, or `?import&url&inline` are appended. ### PoC 1. Start the dev server: `pnpm exec vite root --host 127.0.0.1 --port 5175 --strictPort` 2. Confirm that `server.fs.deny` is enforced (expect 403): `curl -i http://127.0.0.1:5175/src/.env | head -n 20` <img width="3944" height="1092" alt="image" src="https://github.com/user-attachments/assets/ecb9f2e0-e08f-4ac7-b194-e0f988c4cd4f" /> 3. Confirm that the same files can be retrieved with query parameters (expect 200): <img width="2014" height="373" alt="image" src="https://github.com/user-attachments/assets/76bc2a6a-44f4-4161-ae47-eab5ae0c04a8" />

### Summary [`server.fs`](https://vite.dev/config/server-options#server-fs-strict) check was not enforced to the `fetchModule` method that is exposed in Vite dev server's WebSocket. ### 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)) - WebSocket is not disabled by `server.ws: false` Arbitrary files on the server (development machine, CI environment, container, etc.) can be exposed. ### Details If it is possible to connect to the Vite dev server’s WebSocket **without an `Origin` header**, an attacker can invoke `fetchModule` via the custom WebSocket event `vite:invoke` and combine `file://...` with `?raw` (or `?inline`) to retrieve the contents of arbitrary files on the server as a JavaScript string (e.g., `export default "..."`). The access control enforced in the HTTP request path (such as `server.fs.allow`) is not applied to this WebSocket-based execution path. ### PoC 1. Start the dev server on the target Example (used during validation with this repository): ```bash pnpm -C playground/alias exec vite --host 0.0.0.0 --port 5173 ``` 2. Confirm that access is blocked via the HTTP path (example: arbitrary file) ```bash curl -i 'http://localhost:5173/@fs/etc/passwd?raw' ``` Result: `403 Restricted` (outside the allow list) <img width="3898" height="1014" alt="image" src="https://github.com/user-attachments/assets/f6593377-549c-45d7-b562-5c19833438af" /> 3. Confirm that the same file can be retrieved via the WebSocket path By connecting to the HMR WebSocket without an `Origin` header and sending a `vite:invoke` request that calls `fetchModule` with a `file://...` URL and `?raw`, the file contents are returned as a JavaScript module. <img width="1049" height="296" alt="image" src="https://github.com/user-attachments/assets/af969f7b-d34e-4af4-8adb-5e2b83b31972" /> <img width="1382" height="955" alt="image" src="https://github.com/user-attachments/assets/6a230d2e-197a-4c9c-b373-d0129756d5d7" />

### 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" />

MediumVulnerabilityGermanyFranceUnited Kingdom+7#cve#cve-2025-62522#cwe-22

CVE-2025-31125 is a medium severity vulnerability in the Vite frontend tooling framework that exposes sensitive file contents to unauthorized actors. The issue arises when Vite's development server is explicitly exposed to the network using the --host or server.host configuration, allowing attackers to access non-allowed files via ? inline&import or ? raw? import query parameters. This vulnerability affects multiple versions prior to fixed releases 6.2.4, 6.1.

MediumVulnerabilityGermanyFranceNetherlands+4#cve#cve-2025-31125#cwe-200