CVE-2020-7115: ClearPass Policy Manager Auth Bypass Flaw

CVE-2020-7115 Overview

CVE-2020-7115 is a critical authentication bypass vulnerability affecting the Aruba Networks ClearPass Policy Manager web interface. This flaw allows unauthenticated attackers to bypass authentication mechanisms and subsequently execute arbitrary commands on the underlying operating system. ClearPass Policy Manager is a widely deployed network access control (NAC) solution used by enterprises to enforce security policies across wired, wireless, and VPN infrastructures, making this vulnerability particularly dangerous in enterprise environments.

Critical Impact

Successful exploitation enables unauthenticated remote command execution, allowing attackers to fully compromise ClearPass Policy Manager appliances and potentially pivot to connected network infrastructure.

Affected Products

• Aruba Networks ClearPass Policy Manager versions prior to 6.7.13-HF
• Aruba Networks ClearPass Policy Manager versions prior to 6.8.5-HF and 6.8.6
• Aruba Networks ClearPass Policy Manager versions prior to 6.9.1

Discovery Timeline

• 2020-06-03 - CVE-2020-7115 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2020-7115

Vulnerability Analysis

This vulnerability is classified under CWE-306 (Missing Authentication for Critical Function), indicating that the ClearPass Policy Manager web interface fails to properly authenticate users before allowing access to sensitive functionality. The authentication bypass allows attackers to access privileged endpoints without valid credentials, effectively bypassing the security controls designed to protect the management interface.

The network-accessible nature of the vulnerability means that any attacker with network access to the ClearPass Policy Manager web interface can attempt exploitation without requiring any prior authentication or user interaction. Once authentication is bypassed, the attacker gains the ability to execute arbitrary commands on the underlying operating system with the privileges of the ClearPass service.

Root Cause

The root cause of CVE-2020-7115 lies in missing authentication checks for critical functions within the ClearPass Policy Manager web interface. The application fails to properly validate that requests to certain endpoints originate from authenticated sessions, allowing attackers to directly access functionality that should require administrative credentials. This fundamental design flaw in the authentication architecture enables the complete bypass of access controls.

Attack Vector

The attack is network-based and can be executed remotely against any exposed ClearPass Policy Manager web interface. The exploitation flow typically involves:

1. An attacker identifies an exposed ClearPass Policy Manager instance on the network
2. The attacker crafts requests that bypass the authentication mechanisms in the web interface
3. Once authentication is bypassed, the attacker leverages the elevated access to inject and execute operating system commands
4. The attacker achieves full control over the ClearPass appliance, potentially compromising network access control policies and connected infrastructure

The vulnerability requires no privileges, no user interaction, and has low attack complexity, making it highly exploitable in real-world scenarios. Technical details of the exploitation mechanism are documented in the Packet Storm Security Exploit.

Detection Methods for CVE-2020-7115

Indicators of Compromise

• Unexpected authentication attempts or successful logins to ClearPass Policy Manager from unknown IP addresses
• Unusual command execution or process spawning on ClearPass appliances
• Anomalous network traffic originating from ClearPass systems to external destinations
• Unauthorized modifications to ClearPass policies or configuration files

Detection Strategies

• Monitor web server access logs for requests to sensitive endpoints without valid session cookies
• Implement network intrusion detection rules to identify exploitation attempts targeting ClearPass authentication mechanisms
• Deploy endpoint detection and response (EDR) solutions on ClearPass appliances to detect post-exploitation activity
• Review audit logs for command execution events that deviate from normal administrative patterns

Monitoring Recommendations

• Enable comprehensive logging on ClearPass Policy Manager instances and forward logs to a centralized SIEM
• Implement network segmentation to limit exposure of ClearPass management interfaces
• Configure alerting for any authentication bypass attempts or failed authentication patterns
• Regularly audit ClearPass configurations and policies for unauthorized changes

How to Mitigate CVE-2020-7115

Immediate Actions Required

• Upgrade ClearPass Policy Manager to patched versions immediately: 6.7.13-HF, 6.8.5-HF, 6.8.6, 6.9.1 or higher
• Restrict network access to ClearPass Policy Manager web interfaces to trusted management networks only
• Implement firewall rules to block unauthorized access to ClearPass management ports
• Review ClearPass systems for signs of compromise before and after patching

Patch Information

Aruba Networks has released security patches addressing this vulnerability. Organizations should upgrade to the following fixed versions:

• Version 6.7.13-HF for the 6.7.x branch
• Version 6.8.5-HF or 6.8.6 for the 6.8.x branch
• Version 6.9.1 or higher for the 6.9.x branch

Detailed patch information is available in the Aruba Networks Security Advisory (ARUBA-PSA-2020-005).

Workarounds

• Isolate ClearPass Policy Manager systems on dedicated management VLANs with strict access controls
• Implement additional authentication layers such as VPN or jump hosts for administrative access
• Deploy web application firewalls (WAF) to filter malicious requests targeting the ClearPass web interface
• Monitor all access to ClearPass management interfaces until patches can be applied

# Example: Restrict access to ClearPass management interface using iptables
# Allow only trusted management network (adjust IP range as needed)
iptables -A INPUT -p tcp --dport 443 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP