## Vite Dev Server Security Flaw Exposes Denied Files on Windows via Backslash URL
A critical security vulnerability in the Vite development server allows attackers to bypass file access restrictions on Windows systems. The flaw, tracked as CVE-2025-62522, enables the retrieval of files explicitly denied by the `server.fs.deny` configuration if a malicious URL ends with a backslash (`\`). This bypass directly undermines a core security control designed to protect sensitive project files and system directories from unauthorized access during local development.

The vulnerability is specific to Vite's dev server when running on the Windows operating system. It does not affect production builds or servers running on other platforms. The issue was addressed in Vite version 5.4.21, released as a security patch. The update is classified as a patch-level change, indicating a focused fix for this specific security hole rather than a broader feature release.

This exposure highlights the persistent security risks in local development environments, which are often treated as trusted spaces. While the impact is limited to a specific configuration on a single OS, it represents a significant integrity failure for any project relying on `server.fs.deny` to lock down access. Developers and organizations using Vite on Windows must apply the update immediately to close this vector before it can be exploited in targeted attacks against source code or configuration files.
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- **Source**: GitHub Issues
- **Sector**: The Lab
- **Tags**: vulnerability, CVE-2025-62522, dev-server, windows, security-patch
- **Credibility**: unverified
- **Published**: 2026-04-06 12:27:15
- **ID**: 51411
- **URL**: https://whisperx.ai/en/intel/51411