CVE-2022-31529
📋 TL;DR
This vulnerability allows attackers to read arbitrary files on the server through absolute path traversal in the cinemaproject/monorepo repository. It affects any system running this software with vulnerable versions, particularly web applications using the Flask framework. Attackers can exploit this to access sensitive files like configuration files, credentials, or source code.
💻 Affected Systems
- cinemaproject/monorepo
📦 What is this software?
Monorepo by Monorepo Project
⚠️ Risk & Real-World Impact
Worst Case
Complete server compromise through reading sensitive files like SSH keys, database credentials, or configuration files leading to further attacks.
Likely Case
Unauthorized access to sensitive server files containing application secrets, user data, or system information.
If Mitigated
Limited impact with proper file permissions and network segmentation preventing access to critical system files.
🎯 Exploit Status
Exploitation requires sending specially crafted requests to vulnerable endpoints. The vulnerability is well-documented in security advisories.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions after 2021-03-03
Vendor Advisory: https://github.com/github/securitylab/issues/669
Restart Required: Yes
Instructions:
1. Update to latest version of cinemaproject/monorepo repository
2. Ensure Flask send_file calls use safe path validation
3. Restart the application service
🔧 Temporary Workarounds
Implement Path Validation
allAdd input validation to sanitize file paths before passing to send_file function
# In Flask route handler:
# Replace: send_file(requested_path)
# With: send_file(os.path.join(base_dir, sanitized_path))
Web Application Firewall Rules
allBlock requests containing path traversal patterns
# Example WAF rule to block ../ patterns
# ModSecurity: SecRule ARGS "\.\./" "id:1001,phase:2,deny"
🧯 If You Can't Patch
- Implement strict file system permissions to limit accessible directories
- Deploy network segmentation to isolate vulnerable systems from sensitive data
🔍 How to Verify
Check if Vulnerable:
Review Flask route handlers for unsafe send_file usage with user-controlled inputCheck Version:
Check package.json or repository commit history for version date before 2021-03-03Verify Fix Applied:
Test that path traversal attempts return errors instead of file contents📡 Detection & Monitoring
Log Indicators:
- HTTP requests containing ../ patterns
- Unusual file access patterns from web endpoints
- Errors from send_file function with invalid paths
Network Indicators:
- HTTP requests with encoded path traversal sequences (%2e%2e%2f)
- Multiple failed file access attempts
SIEM Query:
source="web_logs" AND (uri="*../*" OR uri="*..%2f*")