CVE-2021-2018
📋 TL;DR
This vulnerability in Oracle Database Server's Advanced Networking Option allows unauthenticated attackers with network access via Oracle Net to potentially compromise the component. It affects Oracle Database Server versions 18c and 19c on Windows platforms only, requiring human interaction from someone other than the attacker to exploit.
💻 Affected Systems
- Oracle Database Server
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete takeover of the Advanced Networking Option component, potentially leading to full system compromise with confidentiality, integrity, and availability impacts across connected systems.
Likely Case
Limited compromise of the Advanced Networking Option component due to the high attack complexity and requirement for human interaction, potentially affecting database networking functionality.
If Mitigated
Minimal impact if proper network segmentation, access controls, and patching are implemented, with the human interaction requirement providing additional protection.
🎯 Exploit Status
Exploitation requires human interaction from someone other than the attacker, making real-world attacks more difficult despite the unauthenticated nature.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Apply Critical Patch Update for January 2021 or later
Vendor Advisory: https://www.oracle.com/security-alerts/cpujan2021.html
Restart Required: Yes
Instructions:
1. Download the appropriate Critical Patch Update from Oracle Support. 2. Apply the patch following Oracle's patching procedures. 3. Restart the Oracle Database service. 4. Verify the patch was successfully applied.
🔧 Temporary Workarounds
Network Segmentation
allRestrict network access to Oracle Database servers to only trusted sources
Use firewall rules to limit access to Oracle Net ports (typically 1521)
Disable Advanced Networking Option
windowsIf not required, disable the Advanced Networking Option component
Modify Oracle configuration to disable Advanced Networking Option features
🧯 If You Can't Patch
- Implement strict network access controls to limit Oracle Net traffic to trusted sources only
- Monitor for suspicious Oracle Net connections and unusual Advanced Networking Option activity
🔍 How to Verify
Check if Vulnerable:
Check Oracle Database version and patch level: SELECT * FROM v$version; and review patch historyCheck Version:
SELECT * FROM v$version;Verify Fix Applied:
Verify the January 2021 Critical Patch Update or later is installed and check patch status in Oracle inventory📡 Detection & Monitoring
Log Indicators:
- Unusual Oracle Net connection attempts
- Advanced Networking Option component errors or crashes
- Unexpected configuration changes to networking components
Network Indicators:
- Suspicious traffic patterns on Oracle Net ports
- Connection attempts from unexpected sources
SIEM Query:
source="oracle_database" AND (event_type="connection_attempt" OR component="Advanced Networking Option")