CVE-2022-31563
📋 TL;DR
This vulnerability allows attackers to perform absolute path traversal attacks in the whmacmac/vprj GitHub repository, enabling unauthorized file access. It affects users running this software through April 6, 2022, due to unsafe use of Flask's send_file function.
💻 Affected Systems
- whmacmac/vprj GitHub repository
📦 What is this software?
Vprj by Vprj Project
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through arbitrary file read, potentially leading to sensitive data exposure, credential theft, or remote code execution.
Likely Case
Unauthorized access to sensitive files on the server, including configuration files, source code, or user data.
If Mitigated
Limited impact with proper file system permissions and input validation in place.
🎯 Exploit Status
Path traversal vulnerabilities are commonly exploited and require minimal technical skill.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions after 2022-04-06
Vendor Advisory: https://github.com/github/securitylab/issues/669
Restart Required: Yes
Instructions:
1. Update to the latest version of whmacmac/vprj repository. 2. Ensure Flask send_file calls include proper path validation. 3. Restart the application service.
🔧 Temporary Workarounds
Input Validation Middleware
allAdd middleware to validate and sanitize file paths before processing.
# Python Flask middleware example
from flask import request, abort
import os
@app.before_request
def validate_path():
if 'file' in request.args:
requested_path = request.args['file']
if not os.path.normpath(requested_path).startswith('/safe/directory/'):
abort(403)
🧯 If You Can't Patch
- Implement strict file system permissions to limit accessible directories.
- Deploy web application firewall (WAF) rules to block path traversal patterns.
🔍 How to Verify
Check if Vulnerable:
Review Flask send_file usage in the codebase for lack of path validation.Check Version:
Check repository commit history or version tags against 2022-04-06.Verify Fix Applied:
Test with path traversal payloads (e.g., '../../etc/passwd') to ensure they are blocked.📡 Detection & Monitoring
Log Indicators:
- Unusual file access patterns, repeated 403/404 errors for traversal attempts
Network Indicators:
- HTTP requests containing '../' sequences or absolute paths
SIEM Query:
source="web_logs" AND (uri="*../*" OR uri="*/etc/*" OR uri="*/windows/*")