CVE-2022-31539
📋 TL;DR
This vulnerability allows attackers to perform absolute path traversal attacks in the kotekan/kotekan repository, enabling unauthorized file access. It affects all users running kotekan versions through 2021.11 due to unsafe use of Flask's send_file function.
💻 Affected Systems
- kotekan/kotekan
📦 What is this software?
Kotekan by Kotekan 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, credentials, and application data.
If Mitigated
Limited impact with proper file system permissions and network segmentation, though the vulnerability still exists.
🎯 Exploit Status
Path traversal vulnerabilities are commonly exploited and require minimal technical skill.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions after 2021.11
Vendor Advisory: https://github.com/kotekan/kotekan/security/advisories
Restart Required: Yes
Instructions:
1. Update kotekan to version after 2021.11
2. Restart the kotekan service
3. Verify the fix by testing path traversal attempts
🔧 Temporary Workarounds
Input Validation
allImplement strict input validation to reject path traversal sequences
File Access Restrictions
linuxConfigure file system permissions to limit kotekan's access to only necessary directories
chmod -R 750 /path/to/kotekan/data
chown -R kotekan:kotekan /path/to/kotekan/data
🧯 If You Can't Patch
- Implement network segmentation to isolate kotekan from sensitive systems
- Deploy web application firewall (WAF) with path traversal protection rules
🔍 How to Verify
Check if Vulnerable:
Check if running kotekan version 2021.11 or earlier, or test with path traversal payloads like '../../etc/passwd'Check Version:
Check kotekan version in application logs or configuration filesVerify Fix Applied:
Test path traversal attempts after patching; they should return 404 or access denied errors📡 Detection & Monitoring
Log Indicators:
- Unusual file access patterns
- Requests containing '../' sequences
- Access to files outside expected directories
Network Indicators:
- HTTP requests with path traversal payloads
- Unusual file download patterns
SIEM Query:
source="kotekan" AND (url="*../*" OR status=404 AND url="*/etc/*")