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Mitsubishi Electric MELSEC iQ-F Series

HIGH
CVSS 7.5
Date 2026-06-18T06:00:00+00:00
Source cisa-csaf
Published by CISA

// Description

Successful exploitation of this vulnerability could allow a remote attacker to cause a denial-of-service (DoS) condition in the affected product by rapidly establishing a large number of TCP connections to it, resulting in an inconsistency in the product's internal connection management process and triggering improper memory access.

// Vulnerabilities (1)

CVE ID CVSS Score Severity Description
CVE-2026-8805 7.5 high
An integer overflow or wraparound vulnerability exists in the EtherNet/IP function of MELSEC iQ-F Series EtherNet/IP module. This vulnerability could allow a remote attacker to cause a denial-of-service condition in the affected product by rapidly establishing a large number of TCP connections to it, resulting in an inconsistency in the product's internal connection management process and triggering improper memory access.

// Remediations (6)

Mitigation: For users who cannot immediately update the product, Mitsubishi Electric recommends using a firewall
For users who cannot immediately update the product, Mitsubishi Electric recommends using a firewall, virtual private network (VPN), etc. to prevent unauthorized access when internet access is required, to minimize the risk of exploiting this vulnerability.
Mitigation: For users who cannot immediately update the product, Mitsubishi Electric recommends using the affect
For users who cannot immediately update the product, Mitsubishi Electric recommends using the affected product within a LAN and blocking access from untrusted networks and hosts through firewalls, to minimize the risk of exploiting this vulnerability.
Mitigation: For users who cannot immediately update the product, Mitsubishi Electric recommends installing anti-
For users who cannot immediately update the product, Mitsubishi Electric recommends installing anti-virus software on PCs that can access the affected product, to minimize the risk of exploiting this vulnerability.
Mitigation: For users who cannot immediately update the product, Mitsubishi Electric recommends using the IP fil
For users who cannot immediately update the product, Mitsubishi Electric recommends using the IP filter function of the affected product to block access from untrusted hosts and minimize the risk of exploiting this vulnerability. For details on the IP filter function, refer to "13.1 IP Filter Function" in the MELSEC iQ-F FX5 User's Manual (Communication) which can be downloaded from the link "https://www.mitsubishielectric.com/fa/download/index.html."
Mitigation: For users who cannot immediately update the product, Mitsubishi Electric recommends restricting phys
For users who cannot immediately update the product, Mitsubishi Electric recommends restricting physical access to the affected product, as well as to PCs and network devices to which it is connected, to minimize the risk of exploiting this vulnerability.
Patch: Mitsubishi Electric is releasing fixed version 1.001 or later for MELSEC iQ-F Series FX5-EIP EtherNe
Mitsubishi Electric is releasing fixed version 1.001 or later for MELSEC iQ-F Series FX5-EIP EtherNet/IP Module FX5-EIP. Download the update file for the fixed version from the link "https://www.mitsubishielectric.com/fa/download/index.html" and install it. For more information on the fixed version, refer to the Mitsubishi Electric security advisory at "https://www.mitsubishielectric.com/psirt/vulnerability/pdf/2026-002_en.pdf".

// References