CVE-2020-26553
📋 TL;DR
This vulnerability allows attackers to upload arbitrary files to the web server directory in Aviatrix Controller versions before R6.0.2483. This can lead to remote code execution, data theft, or complete system compromise. Organizations using vulnerable Aviatrix Controller versions are affected.
💻 Affected Systems
- Aviatrix Controller
📦 What is this software?
Controller by Aviatrix
⚠️ Risk & Real-World Impact
Worst Case
Complete system takeover via web shell upload leading to lateral movement, data exfiltration, and persistent backdoor installation.
Likely Case
Remote code execution allowing attackers to execute arbitrary commands, install malware, or pivot to internal networks.
If Mitigated
Limited impact with proper network segmentation, file upload restrictions, and web application firewalls in place.
🎯 Exploit Status
Exploitation requires only HTTP requests to vulnerable API endpoints. Public technical details available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: R6.0.2483 and later
Vendor Advisory: https://docs.aviatrix.com/HowTos/security_bulletin_article.html#cve-2020-26553
Restart Required: Yes
Instructions:
1. Backup current configuration. 2. Download Aviatrix Controller version R6.0.2483 or later. 3. Follow Aviatrix upgrade documentation. 4. Restart controller services. 5. Verify version and functionality.
🔧 Temporary Workarounds
Web Application Firewall Rules
allBlock or restrict access to vulnerable API endpoints using WAF rules.
# Example WAF rule to block file upload APIs
SecRule REQUEST_URI "@contains /api/v1/upload" "id:1001,phase:1,deny"
Network Access Control
linuxRestrict network access to Aviatrix Controller management interface.
# Example iptables rule
iptables -A INPUT -p tcp --dport 443 -s trusted_networks -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP
🧯 If You Can't Patch
- Isolate Aviatrix Controller behind firewall with strict inbound/outbound rules
- Implement file integrity monitoring on web directories and alert on unauthorized file uploads
🔍 How to Verify
Check if Vulnerable:
Check Aviatrix Controller version via web interface or CLI. If version is below R6.0.2483, system is vulnerable.Check Version:
aviatrix_controller --version or check web admin interfaceVerify Fix Applied:
Confirm version is R6.0.2483 or higher and test file upload functionality to vulnerable endpoints returns proper error.📡 Detection & Monitoring
Log Indicators:
- Unusual file uploads to web directories
- HTTP requests to /api/v1/upload endpoints
- Web shell file creation in web root
Network Indicators:
- HTTP POST requests to upload APIs from unauthorized sources
- Unusual outbound connections from controller
SIEM Query:
source="aviatrix" AND (uri="/api/v1/upload" OR filepath="*.php" OR filepath="*.jsp")