CVE-2020-23620
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code on Orlansoft ERP systems by sending malicious serialized Java objects to the Java Remote Management Interface. All versions of Orlansoft ERP are affected, making it critical for organizations using this software.
💻 Affected Systems
- Orlansoft ERP
📦 What is this software?
Orlansoft Erp by Orlansoft
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with full administrative access, data theft, ransomware deployment, and lateral movement across the network.
Likely Case
Remote code execution leading to data exfiltration, installation of backdoors, or cryptominers on vulnerable servers.
If Mitigated
Limited impact with proper network segmentation and access controls, potentially only affecting the ERP application itself.
🎯 Exploit Status
Multiple public exploit tools exist (like jexboss) that can exploit Java deserialization vulnerabilities with minimal technical skill required.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://orlansoft.com/
Restart Required: Yes
Instructions:
1. Check Orlansoft website for security updates
2. Apply any available patches
3. Restart the ERP application
4. Verify the fix by testing for the vulnerability
🔧 Temporary Workarounds
Disable Java Remote Management Interface
allDisable the vulnerable Java Remote Management Interface if not required for operations
Modify Java configuration to disable JMX/RMI services
Set com.sun.management.jmxremote=false in Java startup parameters
Network Segmentation
linuxRestrict network access to the ERP system's management interface
iptables -A INPUT -p tcp --dport [JMX_PORT] -j DROP
firewall-cmd --permanent --add-rich-rule='rule family="ipv4" source address="[TRUSTED_IP]" port protocol="tcp" port="[JMX_PORT]" accept'
🧯 If You Can't Patch
- Implement strict network access controls to limit who can reach the Java Remote Management Interface
- Deploy a Web Application Firewall (WAF) with rules to detect and block Java deserialization attacks
🔍 How to Verify
Check if Vulnerable:
Test if the Java Remote Management Interface accepts serialized objects using tools like ysoserial or manually by attempting deserialization payloadsCheck Version:
Check Orlansoft ERP version from admin interface or application logsVerify Fix Applied:
Attempt to exploit the vulnerability using known payloads and verify they no longer work📡 Detection & Monitoring
Log Indicators:
- Java deserialization errors in logs
- Unexpected Java class loading
- Suspicious RMI/JMX connections
Network Indicators:
- Unusual traffic to Java RMI ports (typically 1099, 1098)
- Large serialized objects being sent to management interface
SIEM Query:
source="*erp*" AND ("java.io.Serializable" OR "InvocationTargetException" OR "ClassNotFoundException")