CVE-2020-11851
📋 TL;DR
CVE-2020-11851 is a critical remote code execution vulnerability in Micro Focus ArcSight Logger affecting all versions before 7.1.1. Attackers can remotely execute arbitrary code on vulnerable systems without authentication. All organizations running affected ArcSight Logger versions are at risk.
💻 Affected Systems
- Micro Focus ArcSight Logger
📦 What is this software?
Arcsight Logger by Microfocus
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise allowing attackers to execute arbitrary commands, install malware, steal sensitive data, pivot to other systems, and maintain persistent access.
Likely Case
Remote attackers gain shell access to the Logger server, potentially compromising security monitoring capabilities and using the system as a foothold for further attacks.
If Mitigated
With proper network segmentation and access controls, impact could be limited to the Logger system itself, though it remains a significant security risk.
🎯 Exploit Status
CVSS 9.8 indicates trivial exploitation with no authentication required. Public exploit code exists for this vulnerability.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 7.1.1
Vendor Advisory: https://community.microfocus.com/t5/Logger/Logger-Release-Notes-7-1-1/ta-p/2837600
Restart Required: Yes
Instructions:
1. Download ArcSight Logger 7.1.1 from Micro Focus support portal. 2. Backup current configuration and data. 3. Stop Logger services. 4. Install the 7.1.1 update. 5. Restart services and verify functionality.
🔧 Temporary Workarounds
Network Segmentation
allRestrict network access to ArcSight Logger to only trusted management networks and required client systems.
Access Control Lists
allImplement strict firewall rules to limit inbound connections to Logger from authorized IP addresses only.
🧯 If You Can't Patch
- Immediately isolate the Logger system from internet access and restrict internal network access to only essential systems.
- Implement additional monitoring and alerting specifically for suspicious activity on the Logger system.
🔍 How to Verify
Check if Vulnerable:
Check the Logger version via web interface (Admin > About) or command line. If version is below 7.1.1, the system is vulnerable.Check Version:
On Linux: cat /opt/arcsight/logger/current/version.txtVerify Fix Applied:
After patching, verify version shows 7.1.1 or higher and test Logger functionality remains operational.📡 Detection & Monitoring
Log Indicators:
- Unusual process execution from Logger web services
- Suspicious command execution patterns in system logs
- Unexpected network connections originating from Logger
Network Indicators:
- Unusual outbound connections from Logger server
- Exploit-specific payload patterns in network traffic
SIEM Query:
source="arcsight-logger" AND (eventType="Process Execution" OR cmdline="*" | stats count by src_ip, dest_ip, cmdline