CVE-2021-26680
📋 TL;DR
This CVE describes a remote authenticated command injection vulnerability in Aruba ClearPass Policy Manager that allows authenticated attackers to execute arbitrary commands as root on the underlying operating system. Affected organizations are those running ClearPass Policy Manager versions prior to 6.9.5, 6.8.8-HF1, or 6.7.14-HF1.
💻 Affected Systems
- Aruba ClearPass Policy Manager
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with root-level access, allowing attackers to steal sensitive data, deploy persistent backdoors, pivot to other network segments, or disrupt network operations.
Likely Case
Attackers gain full control of the ClearPass server, potentially compromising the entire network authentication infrastructure and accessing credentials, certificates, and network policies.
If Mitigated
Limited impact if proper network segmentation, strict access controls, and monitoring are in place, though the system would still be vulnerable to authenticated attackers.
🎯 Exploit Status
Exploitation requires authenticated access but command injection vulnerabilities are typically straightforward to exploit once authenticated.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 6.9.5, 6.8.8-HF1, or 6.7.14-HF1
Vendor Advisory: https://www.arubanetworks.com/assets/alert/ARUBA-PSA-2021-004.txt
Restart Required: Yes
Instructions:
1. Backup current configuration and data. 2. Download appropriate patched version from Aruba support portal. 3. Apply patch following Aruba's upgrade documentation. 4. Restart ClearPass services. 5. Verify functionality and monitor for issues.
🔧 Temporary Workarounds
Restrict Management Interface Access
allLimit access to ClearPass management interface to trusted administrative networks only using firewall rules.
Implement Strong Authentication Controls
allEnforce multi-factor authentication and strong password policies for all administrative accounts.
🧯 If You Can't Patch
- Implement strict network segmentation to isolate ClearPass servers from other critical systems
- Enhance monitoring and alerting for unusual command execution or authentication patterns
🔍 How to Verify
Check if Vulnerable:
Check ClearPass version via web interface: Admin > Support > System Information, or via CLI: show versionCheck Version:
show versionVerify Fix Applied:
Verify version is 6.9.5, 6.8.8-HF1, or 6.7.14-HF1 or later, and test management interface functionality📡 Detection & Monitoring
Log Indicators:
- Unusual command execution patterns in system logs
- Multiple failed authentication attempts followed by successful login
- Unexpected process execution from web interface user context
Network Indicators:
- Unusual outbound connections from ClearPass server
- Traffic to unexpected ports or IP addresses
SIEM Query:
source="clearpass" AND (event_type="command_execution" OR user="admin" AND action="shell")