CVE-2020-14644: Oracle WebLogic Server RCE Vulnerability

CVE-2020-14644 Overview

CVE-2020-14644 is a critical remote code execution vulnerability in the Oracle WebLogic Server product of Oracle Fusion Middleware, specifically affecting the Core component. This easily exploitable vulnerability allows an unauthenticated attacker with network access via IIOP or T3 protocols to completely compromise vulnerable Oracle WebLogic Server instances. Successful exploitation can result in full takeover of the server, impacting confidentiality, integrity, and availability of the affected system.

Critical Impact

This vulnerability is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, indicating active exploitation in the wild. Unauthenticated remote attackers can achieve complete server takeover via network-accessible T3 or IIOP protocols.

Affected Products

• Oracle WebLogic Server 12.2.1.3.0
• Oracle WebLogic Server 12.2.1.4.0
• Oracle WebLogic Server 14.1.1.0.0

Discovery Timeline

• July 15, 2020 - CVE-2020-14644 published to NVD
• October 27, 2025 - Last updated in NVD database

Technical Details for CVE-2020-14644

Vulnerability Analysis

This vulnerability exists in the Core component of Oracle WebLogic Server and represents a severe security risk due to its ease of exploitation. The vulnerability requires no authentication and can be exploited remotely over the network through the T3 and IIOP protocols, which are commonly used for WebLogic Server communication. The attack complexity is low, meaning attackers do not need special conditions or preparation to successfully exploit this flaw.

When successfully exploited, this vulnerability grants attackers complete control over the affected WebLogic Server instance. The impact spans all three security dimensions: attackers can access sensitive data (confidentiality), modify server configurations and data (integrity), and disrupt services or render the server unavailable (availability).

Root Cause

The vulnerability stems from insecure handling of network requests in the WebLogic Server Core component. The T3 and IIOP protocols, which are binary protocols used for remote method invocation and distributed object communication, fail to properly validate incoming requests. This allows attackers to send specially crafted network packets that bypass security controls and execute arbitrary code on the server.

Attack Vector

The attack vector is network-based, requiring the attacker to have network access to the WebLogic Server's T3 or IIOP listener ports. The T3 protocol typically runs on port 7001 (the default WebLogic administration port), while IIOP may use various configured ports. An attacker exploits this vulnerability by:

1. Identifying an exposed WebLogic Server with T3 or IIOP protocols enabled
2. Crafting malicious network requests targeting the vulnerable Core component
3. Sending the payload to the server without requiring any authentication
4. Achieving remote code execution with the privileges of the WebLogic Server process

The vulnerability does not require user interaction, making it particularly dangerous for internet-facing WebLogic deployments.

Detection Methods for CVE-2020-14644

Indicators of Compromise

• Unexpected network connections to WebLogic Server T3 (typically port 7001) or IIOP ports from external or unknown IP addresses
• Anomalous process spawning from the WebLogic Server Java process
• Unusual outbound network connections originating from the WebLogic Server
• Suspicious log entries in WebLogic Server logs indicating deserialization errors or unauthorized access attempts

Detection Strategies

• Monitor network traffic for unusual T3 or IIOP protocol communications, especially from untrusted sources
• Implement intrusion detection system (IDS) rules to detect exploitation attempts targeting WebLogic Server protocols
• Review WebLogic Server access logs for patterns indicating reconnaissance or exploitation attempts
• Deploy endpoint detection and response (EDR) solutions to identify post-exploitation activity

Monitoring Recommendations

• Enable detailed logging for WebLogic Server T3 and IIOP protocol handlers
• Configure alerts for failed authentication attempts and suspicious network patterns on WebLogic ports
• Implement network segmentation monitoring to detect lateral movement attempts from compromised WebLogic instances
• Regularly audit WebLogic Server configurations and deployed applications for unauthorized changes

How to Mitigate CVE-2020-14644

Immediate Actions Required

• Apply the Oracle Critical Patch Update (CPU) from July 2020 immediately to all affected WebLogic Server installations
• If patching is not immediately possible, disable T3 and IIOP protocols if they are not required for business operations
• Restrict network access to WebLogic Server administration ports using firewalls and network access control lists
• Monitor affected systems for signs of compromise while patching is in progress

Patch Information

Oracle addressed this vulnerability in the July 2020 Critical Patch Update. Organizations should upgrade their WebLogic Server installations to the latest patched versions. This vulnerability is tracked in the CISA Known Exploited Vulnerabilities Catalog, which mandates federal agencies to apply remediations according to established timelines.

Workarounds

• Disable T3 protocol access by configuring connection filters in the WebLogic Server console to block external T3 connections
• Disable IIOP protocol if not required by setting the appropriate configuration in the WebLogic Server administration console
• Implement network-level controls to restrict access to WebLogic Server ports (7001/7002) to trusted internal networks only
• Consider deploying a web application firewall (WAF) with rules to filter malicious T3/IIOP traffic

# Example: WebLogic connection filter to restrict T3 access
# Add to config.xml or configure via WebLogic Console
# Navigate to: Environment > Servers > [server_name] > Protocols > General
# Enable "Connection Filter" and add rules:
# 
# Allow only internal network access to T3 protocol:
# 10.0.0.0/8 * * allow t3 t3s
# 192.168.0.0/16 * * allow t3 t3s
# 0.0.0.0/0 * * deny t3 t3s