CVE-2026-13584: Improper Enforcement of Message Integrity During Transmission in a Communication Channel vulnerability in Mitsubishi Electric MELSEC MX Controller MX-R model, M

Improper Enforcement of Message Integrity During Transmission in a Communication Channel vulnerability in Mitsubishi Electric MELSEC MX Controller MX-R model, M

Improper Enforcement of Message Integrity During Transmission in a Communication Channel vulnerability in Mitsubishi Electric MELSEC MX Controller MX-R model, MELSEC MX Controller MX-F model, Master/local module, CC-Link IE TSN interface board, Motion module, MELSEC iQ-L Series Motion Module, Motion Control Board, Block-type remote module, Block-type remote module with safety functions, Analog-Digital converter module, Digital-Analog converter module, CC-Link IE TSN compatible coupler, FPGA module, Tension meter, AC Servo MELSERVO-J5, AC Servo MELSERVO-JET, Liner Track System MTR-S series Linear track control module, Inverter FR-A800/F800/E800 Series, Industrial Robot CR800-D series controller Network Base Card, CC-Link IE TSN expansion unit, CC-Link IE TSN-CC-Link IE Field Network bridge module, CC-Link IE TSN-AnyWireASLINK bridge module, Energy Measuring Unit CC-Link IE TSN Communication Unit, GOT3000 Series, CC-Link IE TSN Communication Unit, Motion Control Software, CC-Link IE TSN Communication Software for Windows, Analysis Support Software MELSOFT VIMA, Master/Local module Designated communication LSI DeviceKit, Remote Station Communication LSI with GbE-PHY, CC-Link IE TSN Ma

Description from the National Vulnerability Database, published by Mitsubishielectric.Psirt@yd.MitsubishiElectric.co.jp

What it means for a small business

If your business uses MELSEC MX Controller MX-R model MXR300-16, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.19%, higher than 8% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 29, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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