CVE-2024-31207: Vite Information Disclosure Vulnerability

CVE-2024-31207 Overview

CVE-2024-31207 is an information disclosure vulnerability affecting Vite, a popular frontend build tool used to improve the frontend development experience. The vulnerability exists in the server.fs.deny configuration option, which is designed to restrict access to sensitive files during development. However, due to improper path handling, this security control fails to deny requests for patterns that include directories, potentially allowing attackers to access sensitive files on the development server.

Critical Impact

Attackers can bypass the server.fs.deny security control to access sensitive files on the Vite development server, potentially exposing configuration files, source code, environment variables, or other confidential information.

Affected Products

• Vite versions prior to 5.2.6
• Vite versions prior to 5.1.7
• Vite versions prior to 5.0.13
• Vite versions prior to 4.5.3
• Vite versions prior to 3.2.10
• Vite versions prior to 2.9.18

Discovery Timeline

• 2024-04-04 - CVE-2024-31207 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2024-31207

Vulnerability Analysis

This vulnerability is classified under CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor). The issue stems from how Vite's development server processes file access requests when the server.fs.deny configuration is used to restrict access to specific file patterns.

The server.fs.deny option is intended to provide a security layer that prevents the development server from serving files matching specified patterns. However, the implementation contains a flaw in how it handles patterns that include directory paths. When an attacker crafts a request using directory traversal or specific path patterns, the deny list validation can be circumvented, allowing unauthorized access to files that should be protected.

This vulnerability requires network access and exploiting it successfully depends on specific conditions being met, which introduces some complexity to the attack. However, if successfully exploited, the confidentiality impact is significant as it can lead to exposure of sensitive files.

Root Cause

The root cause of this vulnerability lies in the inadequate path pattern matching logic within Vite's file system access control mechanism. The server.fs.deny implementation does not properly normalize or validate request paths that contain directory components before comparing them against the deny patterns. This oversight allows attackers to craft file requests that semantically match protected patterns but syntactically bypass the pattern matching logic.

Attack Vector

The attack vector is network-based, requiring the attacker to have access to the Vite development server. Exploitation involves sending crafted HTTP requests to the development server with file paths that include directory patterns designed to bypass the server.fs.deny restrictions.

An attacker could target commonly sensitive files such as:

• Environment files (.env, .env.local, .env.production)
• Configuration files containing secrets or API keys
• Source code files that may contain hardcoded credentials
• Private keys or certificates in the project directory

The attack does not require authentication or user interaction, but the complexity is considered high due to the specific conditions that must be present for successful exploitation.

Detection Methods for CVE-2024-31207

Indicators of Compromise

• Unusual HTTP requests to the Vite development server containing directory traversal patterns
• Access logs showing requests for sensitive files like .env, configuration files, or source files outside the expected serve directory
• Requests with unusual path patterns attempting to access files typically restricted by server.fs.deny

Detection Strategies

• Monitor Vite development server access logs for suspicious file access requests containing ../ or unusual directory patterns
• Implement network monitoring to detect anomalous HTTP requests targeting development server ports (typically 5173 or configured Vite port)
• Review access patterns for attempts to read environment files, configuration files, or other sensitive resources
• Deploy web application firewalls (WAF) configured to detect path traversal attempts

Monitoring Recommendations

• Enable verbose logging on Vite development servers to capture detailed request information
• Set up alerts for access attempts to sensitive file patterns (.env*, *.key, config.*)
• Monitor for repeated failed or unusual file access requests from external IP addresses
• Ensure development servers are not exposed to untrusted networks where possible

How to Mitigate CVE-2024-31207

Immediate Actions Required

• Update Vite to a patched version: 5.2.6, 5.1.7, 5.0.13, 4.5.3, 3.2.10, or 2.9.18 depending on your major version
• Audit development environments to ensure Vite servers are not exposed to untrusted networks
• Review server.fs.deny configurations to verify intended files are properly protected after patching
• Restrict network access to Vite development servers to trusted local networks or localhost only

Patch Information

The Vite team has released patches across multiple version branches to address this vulnerability. Users should update to the following minimum versions:

For detailed patch information, refer to the GitHub Security Advisory GHSA-8jhw-289h-jh2g.

Workarounds

• Ensure Vite development servers are bound to localhost only and not exposed to external networks
• Use a reverse proxy with additional path validation to filter malicious requests before they reach the Vite server
• Avoid storing sensitive files (credentials, API keys, private keys) in directories accessible to the Vite development server
• Implement network segmentation to isolate development environments from untrusted networks

# Verify Vite version and update to patched release
npm list vite
npm update vite@latest

# Or for specific version branches
npm install vite@5.2.6  # For 5.2.x users
npm install vite@5.1.7  # For 5.1.x users
npm install vite@4.5.3  # For 4.x users