CVE-2023-7033 in MELSEC iQ-F Series FX5U-32MT
Summary
by MITRE • 02/27/2024
Insufficient Resource Pool vulnerability in Ethernet function of Mitsubishi Electric Corporation MELSEC iQ-R series CPU module, MELSEC iQ-L series CPU module, MELSEC iQ-R Ethernet Interface Module, MELSEC iQ-R CC-Link IE TSN Master/Local Module, CC-Link IE TSN Remote I/O Module, CC-Link IE TSN Analog-Digital Converter Module, CC-Link IE TSN Digital-Analog Converter Module, CC-Link IE TSN - CC-Link IE Field Network Bridge Module, CC-Link IE TSN - AnyWireASLINK Bridge Module, CC-Link IE TSN FPGA Module, CC-Link IE TSN Remote Station Communication LSI CP620 with GbE-PHY, MELSEC iQ-R Motion Module, MELSEC iQ-L Motion Module, MELSEC iQ-F FX5 Motion Module, MELSEC iQ-F Series CPU module, MELSEC iQ-F Series Ethernet module, MELSEC iQ-F Series Ethernet/IP module, MELSEC iQ-F Series OPC UA Module, MELSEC iQ-F Series CC-Link IE TSN master/local module, GOT2000 Series CC-Link IE TSN Communication Unit, FR-A800-E series inverters, FR-F800-E series inverters, FR-E800-E series inverters, INVERTER CC-Link IE TSN Plug-in option, INVERTER CC-Link IE TSN Safety Plug-in option, INVERTER CC-Link IE TSN communication function built-in type, MR-J5 series AC Servos MELSERVO, MR-JET series AC Servos MELSERVO, MR-MD333G series AC Servos MELSERVO, MR-JE series AC Servos MELSERVO, MELSERVO-J4 AC Servos MELSERVO and Embedded Type Servo System Controller allow a remote attacker to cause a temporary Denial of Service condition for a certain period of time in Ethernet communication of the products by performing TCP SYN Flood attack.
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Analysis
by VulDB Data Team • 04/15/2026
The vulnerability identified as CVE-2023-7033 represents a critical insufficient resource pool weakness affecting multiple Mitsubishi Electric Corporation industrial automation products within the MELSEC iQ-R and iQ-L series platforms. This flaw specifically targets the Ethernet communication functions of these industrial control systems, creating a pathway for remote attackers to disrupt operational continuity through deliberate resource exhaustion attacks. The affected product portfolio spans across various CPU modules, Ethernet interface modules, communication bridge modules, motion modules, and servo systems, indicating a widespread impact across Mitsubishi's industrial control ecosystem.
The technical mechanism underlying this vulnerability involves the exploitation of TCP SYN Flood attack vectors against the Ethernet communication protocols implemented in these industrial devices. When subjected to sustained SYN flood attacks, the affected systems experience temporary denial of service conditions as their network connection handling resources become exhausted. This resource pool exhaustion prevents legitimate network connections from being established, effectively disrupting the communication pathways essential for industrial process control and monitoring operations. The vulnerability's classification aligns with CWE-400, which addresses "Uncontrolled Resource Consumption" in software systems, specifically targeting the inadequate management of network connection resources within industrial control environments.
The operational impact of this vulnerability extends beyond simple service disruption to potentially compromise industrial process integrity and safety systems. In manufacturing environments where continuous operation is critical, even temporary denial of service conditions can result in production halts, quality control issues, and potential safety risks. The remote nature of the attack vector means that adversaries can exploit this weakness from external networks without requiring physical access to the industrial facilities, making the threat landscape particularly concerning for critical infrastructure sectors. This vulnerability affects not only the core control systems but also the extensive network of connected devices including inverters, servo drives, and communication units that form the backbone of modern industrial automation systems.
Security practitioners should implement immediate mitigations including network segmentation, firewall rules to limit TCP SYN flood attacks, and monitoring of network connection patterns for anomalous behavior. The affected products should be updated with vendor-provided patches as soon as they become available, and network administrators should consider implementing rate limiting and SYN cookies mechanisms to protect against TCP SYN flood attacks. Organizations should also conduct comprehensive risk assessments to identify all affected devices within their industrial control networks and establish incident response procedures specifically tailored to address denial of service conditions in industrial environments. This vulnerability demonstrates the critical importance of securing industrial communication protocols and highlights the need for robust resource management in embedded systems used in critical infrastructure environments, aligning with ATT&CK technique T1499 for network denial of service attacks and emphasizing the necessity of protecting industrial control systems from remote exploitation vectors.