CVE-2025-31125: Vite Vitejs Improper Access Control Vulnerability

Vite is a development server and build tool used in many JavaScript and TypeScript projects. CVE-2025-31125 is an improper access control weakness that can let an attacker retrieve the contents of files that should remain inaccessible when the Vite development server is deliberately exposed to the network.

How it works

The vulnerability is classified under CWE-200 and CWE-284. It stems from insufficient access control checks in the handling of specific query parameters on the development server. An attacker who can reach the server may request files using the parameters ?inline&import or ?raw?import and receive their contents even when those files are outside the intended public directory or otherwise restricted.

Exploitation requires the server to be reachable from the network. The issue does not affect typical local-only usage.

Am I affected? How to find it in your systems

Vite runs as a local development server during application development and testing. It is commonly present in frontend codebases that use modern JavaScript frameworks. Begin by searching project files for vite.config, package.json entries that list vite as a dependency, or scripts that invoke the vite command.

• Check whether any development or test environments start the server with the --host flag or set server.host in the configuration file.
• Inventory all instances where the development server is reachable from outside localhost.
• Review network-accessible development environments, CI pipelines that expose ports, and any cloud or container deployments that forward the Vite port.
• Look for access logs showing requests containing ?inline&import or ?raw?import to identify possible prior attempts.

Exact affected versions and configurations must be confirmed against the vendor advisory.

How to remediate

Apply the vendor-supplied update referenced in the official advisory. After patching, review all Vite configurations and remove or restrict any use of --host or server.host unless network exposure is explicitly required and additional controls are in place.

• Limit the development server to localhost in all non-production environments.
• Use separate build and preview commands for sharing artifacts rather than exposing the live development server.
• Ensure that any required network access is mediated by authentication or network-level controls rather than direct exposure.

If you can't patch immediately

Until the update can be applied, prevent network exposure of the development server. Block inbound connections to the Vite port at the host firewall or container network policy. If temporary network access is unavoidable, place the server behind an authenticated reverse proxy or VPN and monitor logs for the specific query parameters mentioned above.

• Disable the development server when it is not actively in use.
• Segment development networks so that only trusted workstations can reach the server.
• Enable verbose logging on the server and forward logs to a central system for detection of anomalous file requests.

If your data may have been exposed

Actively exploited vulnerabilities of this type can lead to unauthorized access to source code or configuration files. Organizations can run a free exposure scan of their email domains against known breach data to check for related incidents.