CVE-2016-9363 in NPort
Summary
by MITRE
An issue was discovered in Moxa NPort 5110 versions prior to 2.6, NPort 5130/5150 Series versions prior to 3.6, NPort 5200 Series versions prior to 2.8, NPort 5400 Series versions prior to 3.11, NPort 5600 Series versions prior to 3.7, NPort 5100A Series & NPort P5150A versions prior to 1.3, NPort 5200A Series versions prior to 1.3, NPort 5150AI-M12 Series versions prior to 1.2, NPort 5250AI-M12 Series versions prior to 1.2, NPort 5450AI-M12 Series versions prior to 1.2, NPort 5600-8-DT Series versions prior to 2.4, NPort 5600-8-DTL Series versions prior to 2.4, NPort 6x50 Series versions prior to 1.13.11, NPort IA5450A versions prior to v1.4. Buffer overflow vulnerability may allow an unauthenticated attacker to remotely execute arbitrary code.
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Analysis
by VulDB Data Team • 06/03/2026
The vulnerability identified as CVE-2016-9363 represents a critical buffer overflow flaw affecting multiple Moxa NPort series industrial network devices. This security weakness resides in the device's handling of network packets and specifically impacts firmware versions prior to the specified updates for various NPort models including 5110, 5130/5150, 5200, 5400, 5600, 5100A, 5200A, 5150AI-M12, 5250AI-M12, 5450AI-M12, 5600-8-DT, 5600-8-DTL, 6x50, and IA5450A series devices. The flaw manifests when the device processes incoming network traffic without proper input validation, creating an exploitable condition that allows attackers to overwrite memory locations beyond the intended buffer boundaries.
This buffer overflow vulnerability falls under the Common Weakness Enumeration category CWE-121, which describes stack-based buffer overflow conditions where insufficient bounds checking allows attackers to write beyond allocated memory regions. The vulnerability's impact extends beyond simple denial of service as it enables remote code execution without requiring authentication, making it particularly dangerous in industrial control environments where these devices often operate with minimal security controls. The attack vector operates through network communication protocols that the affected devices process, allowing unauthenticated remote exploitation from any location on the network.
The operational implications of this vulnerability are severe for industrial environments where Moxa NPort devices serve as critical communication bridges between field devices and enterprise networks. These devices typically function as serial-to-ethernet gateways in manufacturing, energy, and infrastructure control systems, making them attractive targets for adversaries seeking to compromise industrial control systems. The ability to execute arbitrary code remotely without authentication means attackers could potentially gain complete control over the affected devices, leading to data exfiltration, system disruption, or even physical damage to industrial processes. The vulnerability's presence in multiple device series also indicates a systemic flaw in the firmware development practices across Moxa's industrial networking product line.
Mitigation strategies for CVE-2016-9363 require immediate firmware updates to the specified versions or later releases that address the buffer overflow condition. Network segmentation and access controls should be implemented to limit exposure of these devices to untrusted networks, particularly in industrial environments where physical security is paramount. The vulnerability aligns with ATT&CK technique T1203, which describes exploiting software vulnerabilities for remote code execution, and represents a significant risk to industrial cybersecurity frameworks. Organizations should conduct comprehensive inventory assessments to identify all affected devices across their networks, implement network monitoring to detect exploitation attempts, and establish incident response procedures specific to industrial control system compromises. Additionally, the vulnerability demonstrates the importance of secure software development practices and regular security assessments in industrial networking equipment to prevent similar issues in future firmware releases.