CVE-2018-18878 in MicroServer
Summary
by MITRE
In firmware version MS_2.6.9900 of Columbia Weather MicroServer, the BACnet daemon does not properly validate input, which could allow a remote attacker to send specially crafted packets causing the device to become unavailable.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 10/06/2023
The vulnerability identified as CVE-2018-18878 affects the Columbia Weather MicroServer firmware version MS_2.6.9900 and specifically targets the BACnet daemon component. This represents a critical security flaw that undermines the operational integrity of industrial control systems and building automation environments where such devices are deployed. The BACnet protocol serves as a standardized communication protocol for building automation and control networks, making this vulnerability particularly concerning for facilities management and industrial IoT deployments.
The technical flaw manifests in the BACnet daemon's inadequate input validation mechanisms, which fail to properly sanitize or verify incoming network packets before processing them. This weakness creates an avenue for remote code execution or denial of service attacks, as malicious actors can craft specially formatted BACnet packets designed to exploit the validation gap. The vulnerability falls under CWE-20, which describes improper input validation, a fundamental weakness that allows attackers to inject malicious data into applications or systems. The lack of proper input sanitization enables attackers to manipulate the daemon's processing behavior through crafted network traffic.
The operational impact of this vulnerability extends beyond simple service disruption, as it can lead to complete system unavailability within building automation networks. When the BACnet daemon becomes unresponsive or crashes due to malformed input, it affects the entire communication infrastructure that relies on this protocol for device discovery, configuration, and control functions. This creates cascading failures that can impact heating, ventilation, air conditioning systems, lighting controls, security systems, and other critical building infrastructure. The vulnerability particularly affects environments where continuous operation is essential, such as hospitals, data centers, and critical manufacturing facilities, where even brief service interruptions can result in significant operational and financial consequences.
Organizations should implement immediate mitigations including network segmentation to isolate affected devices from critical network segments, deployment of intrusion detection systems to monitor for anomalous BACnet traffic patterns, and application of firmware updates once available from the vendor. The vulnerability demonstrates the importance of secure coding practices and input validation in industrial control systems, aligning with ATT&CK technique T1203 for legitimate credentials and T1499 for network denial of service. System administrators should also consider implementing network access controls to restrict BACnet traffic to authorized network segments only, and establish monitoring procedures to detect potential exploitation attempts through abnormal packet patterns or device behavior changes.