CVE-2012-6439 in ControlLogix controllers
Summary
by MITRE
Rockwell Automation EtherNet/IP products; 1756-ENBT, 1756-EWEB, 1768-ENBT, and 1768-EWEB communication modules; CompactLogix L32E and L35E controllers; 1788-ENBT FLEXLogix adapter; 1794-AENTR FLEX I/O EtherNet/IP adapter; ControlLogix 18 and earlier; CompactLogix 18 and earlier; GuardLogix 18 and earlier; SoftLogix 18 and earlier; CompactLogix controllers 19 and earlier; SoftLogix controllers 19 and earlier; ControlLogix controllers 20 and earlier; GuardLogix controllers 20 and earlier; and MicroLogix 1100 and 1400 allow remote attackers to cause a denial of service (control and communication outage) via a CIP message that modifies the (1) configuration or (2) network parameters.
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Analysis
by VulDB Data Team • 07/01/2025
The vulnerability identified as CVE-2012-6439 represents a critical flaw in Rockwell Automation's EtherNet/IP communication products that affects a wide range of industrial control and automation equipment. This vulnerability resides within the Common Industrial Protocol implementation used by these devices, specifically targeting the configuration and network parameter modification capabilities. The affected products span multiple generations of Rockwell Automation controllers including CompactLogix L32E and L35E, ControlLogix systems, GuardLogix controllers, and various EtherNet/IP communication modules such as the 1756-ENBT and 1768-ENBT units. These devices operate within critical industrial environments where reliable communication and control are paramount for operational continuity and safety.
The technical flaw manifests when remote attackers can craft and transmit specially crafted CIP (Common Industrial Protocol) messages that manipulate the configuration or network parameters of the affected devices. This vulnerability falls under CWE-121, which describes a buffer overflow condition, and more specifically aligns with CWE-129, representing an insufficient validation of the length of input data. The flaw allows attackers to modify critical system parameters without proper authentication or authorization, potentially leading to complete system disruption. The CIP protocol, which is fundamental to EtherNet/IP communications, does not properly validate or sanitize the parameters received in certain message types, creating an avenue for malicious actors to manipulate device configurations. This vulnerability is particularly concerning because it operates at the network layer where control systems communicate with each other and with external monitoring systems.
The operational impact of this vulnerability extends far beyond simple service interruption, as it can lead to complete control and communication outages in industrial environments. When an attacker successfully exploits this vulnerability, they can cause devices to reset, reconfigure network settings, or alter operational parameters that may result in production line shutdowns, safety system failures, or complete loss of control over industrial processes. The affected controllers and adapters are commonly deployed in critical infrastructure sectors including manufacturing, oil and gas, water treatment, and power generation where such outages can result in significant financial losses, safety hazards, and operational disruptions. According to ATT&CK framework, this vulnerability maps to T1498 which covers Network Denial of Service, and T1566 which addresses Phishing with Social Engineering, as the attack vector often involves remote exploitation without requiring physical access to the systems. The vulnerability's impact is amplified by the fact that these devices often operate in environments with limited network monitoring and security controls, making detection and prevention more challenging.
Mitigation strategies for CVE-2012-6439 should focus on both immediate protective measures and long-term architectural improvements. Organizations should implement network segmentation to isolate critical control systems from general corporate networks, deploy firewalls and network access controls to restrict unauthorized access to EtherNet/IP ports, and ensure that all affected devices are running the latest firmware versions provided by Rockwell Automation. The vulnerability requires proper input validation and parameter sanitization at the protocol level, which can be achieved through network monitoring tools that can detect anomalous CIP message patterns. Additionally, implementing network intrusion detection systems specifically configured to monitor EtherNet/IP traffic can help identify potential exploitation attempts. Security professionals should also consider the principle of least privilege by restricting network access to only necessary systems and personnel, and maintaining detailed network configuration baselines to quickly detect unauthorized changes. The vulnerability demonstrates the critical need for industrial control system security awareness and proper network architecture design that separates operational technology from information technology environments.