CVE-2021-40999
📋 TL;DR
This CVE allows remote attackers to execute arbitrary commands on Aruba ClearPass Policy Manager systems without authentication. It affects ClearPass Policy Manager versions 6.8.x, 6.9.x, and 6.10.x before specific patched versions. Attackers can potentially gain full control of affected systems.
💻 Affected Systems
- Aruba ClearPass Policy Manager
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise allowing attackers to execute arbitrary commands, steal sensitive data, deploy ransomware, pivot to other network resources, and maintain persistent access.
Likely Case
Remote code execution leading to credential theft, installation of backdoors, and lateral movement within the network environment.
If Mitigated
Limited impact with proper network segmentation, strong access controls, and monitoring in place, potentially containing the attack to isolated segments.
🎯 Exploit Status
The vulnerability allows unauthenticated remote command execution, making it relatively easy to exploit once technical details are known.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 6.8.9-HF1, 6.9.7-HF1, or 6.10.2 depending on current version
Vendor Advisory: https://www.arubanetworks.com/assets/alert/ARUBA-PSA-2021-018.txt
Restart Required: Yes
Instructions:
1. Download the appropriate patch from Aruba support portal. 2. Backup current configuration. 3. Apply patch via ClearPass web interface or CLI. 4. Restart the ClearPass appliance. 5. Verify successful update.
🔧 Temporary Workarounds
Network Access Restriction
linuxRestrict network access to ClearPass Policy Manager to only trusted IP addresses and networks
Use firewall rules to limit access: iptables -A INPUT -p tcp --dport 443 -s trusted_network -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP
🧯 If You Can't Patch
- Implement strict network segmentation and firewall rules to limit access to ClearPass systems
- Enable enhanced logging and monitoring for suspicious activities on ClearPass systems
🔍 How to Verify
Check if Vulnerable:
Check ClearPass version via web interface (Admin > Support > System Information) or CLI command 'show version'Check Version:
show versionVerify Fix Applied:
Verify version is 6.8.9-HF1 or higher for 6.8.x, 6.9.7-HF1 or higher for 6.9.x, or 6.10.2 or higher for 6.10.x📡 Detection & Monitoring
Log Indicators:
- Unusual command execution in system logs
- Unexpected process creation
- Suspicious network connections from ClearPass system
Network Indicators:
- Unusual outbound connections from ClearPass system
- Traffic to unexpected ports or IP addresses
SIEM Query:
source="clearpass" AND (event_type="command_execution" OR process_name="suspicious_process")