CVE-2022-31567
📋 TL;DR
This vulnerability allows attackers to read arbitrary files on the server through path traversal in the DSABenchmark/DSAB repository. It affects users running versions through 2.1 of this software, which uses Flask's send_file function unsafely without proper path validation.
💻 Affected Systems
- DSABenchmark/DSAB
📦 What is this software?
Data Stream Algorithm Benchmark by Data Stream Algorithm Benchmark Project
⚠️ Risk & Real-World Impact
Worst Case
Complete server compromise through reading sensitive files like /etc/passwd, SSH keys, or configuration files containing credentials, potentially leading to remote code execution.
Likely Case
Information disclosure of sensitive server files, potentially exposing credentials, configuration data, or other confidential information.
If Mitigated
Limited impact with proper file system permissions and network segmentation, though information disclosure risk remains.
🎯 Exploit Status
Path traversal vulnerabilities are trivial to exploit with basic HTTP requests. Public GitHub issues demonstrate exploitation techniques.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions after 2.1
Vendor Advisory: https://github.com/github/securitylab/issues/669
Restart Required: Yes
Instructions:
1. Update to the latest version of DSABenchmark/DSAB repository. 2. Restart the Flask application. 3. Verify the fix by testing path traversal attempts.
🔧 Temporary Workarounds
Input Validation Middleware
allAdd middleware to validate and sanitize file paths before they reach send_file function
# Python Flask middleware example
from flask import abort
@app.before_request
def validate_paths():
if '..' in request.path or '~' in request.path:
abort(400)
Web Application Firewall
allConfigure WAF rules to block path traversal patterns
# Example mod_security rule
SecRule REQUEST_URI "@contains .." "id:1001,phase:1,deny,status:403"
🧯 If You Can't Patch
- Implement strict file system permissions to limit accessible directories
- Deploy behind reverse proxy with path sanitization and request filtering
🔍 How to Verify
Check if Vulnerable:
Attempt to access /../../etc/passwd or similar path traversal patterns via the application's file serving endpointsCheck Version:
Check package.json or repository version files for DSABenchmark versionVerify Fix Applied:
Test the same path traversal attempts after patching; they should return 400/403 errors instead of file contents📡 Detection & Monitoring
Log Indicators:
- HTTP requests containing '..' or '~' patterns in URLs
- Unusual file access patterns from single IPs
- 403/400 errors after implementing fixes
Network Indicators:
- HTTP requests with encoded path traversal sequences (%2e%2e%2f)
- Multiple failed attempts to access sensitive paths
SIEM Query:
source="web_logs" AND (url="*..*" OR url="*~*") AND response_code=200