Original Article Summary

View CSAF Summary Successful exploitation of this vulnerability could allow a local attacker to successfully authenticate even with an invalid block password by executing the affected product and modify part of the executable module in memory, and thereby allows the attacker to view, tamper with, destroy, or delete control programs. The following versions of Mitsubishi Electric GX Works3 and Motion Control Settings are affected: Mitsubishi Electric GX Works3 vers:all/* (CVE-2026-15688) Mitsubishi Electric Motion Control Settings (Software packaged with GX Works3) vers:all/* (CVE-2026-15688) CVSS Vendor Equipment Vulnerabilities v3 8.8 Mitsubishi Electric Mitsubishi Electric GX Works3 and Motion Control Settings Incorrect Implementation of Authentication Algorithm Background Critical Infrastructure Sectors: Critical Manufacturing Countries/Areas Deployed: Worldwide Company Headquarters Location: Japan Vulnerabilities Expand All + CVE-2026-15688 Incorrect Implementation of Authentication Algorithm (CWE-303) vulnerability in the affected products allows a local attacker to successfully authenticate even with an invalid block password by executing the affected product and modify part of the executable module in memory, and thereby allows the attacker to view, tamper with, destroy, or delete control programs. View CVE Details Affected Products Mitsubishi Electric GX Works3 and Motion Control Settings Vendor: Mitsubishi Electric Product Version: Mitsubishi Electric GX Works3: vers:all/*, Mitsubishi Electric Motion Control Settings (Software packaged with GX Works3): vers:all/* Product Status: known_affected Remediations Workaround For customers using GX Works3, please download version 1.096A or later from the link https://www.mitsubishielectric.com/fa/download/software/detailsearch.page?mode=software&kisyu=/plceng&shiryoid=1000001411&lang=2&select=0&softid=1&infostatus=1_2_1&viewradio=0&viewstatus=&viewpos=, install it, and set the security version for projects to "2". Please refer to “15.9 Preventing Illegal Access to/Falsification of Data (Security Version)” in “GX Works3 Operating Manual” for details. For more information about the workaround, refer to the Mitsubishi Electric security advisory available at "https://www.mitsubishielectric.com/psirt/vulnerability/pdf/2026-007_en.pdf". Workaround For customers using Motion Control Settings (Software packaged with GX Works3), Please download version 1.070Y or later from the link "https://www.mitsubishielectric.com/fa/download/software/detailsearch.page?mode=software&kisyu=/ssc&shiryoid=1000000803&lang=2&select=0&softid=1&infostatus=1_8_1&viewradio=0&viewstatus=&viewpos=", install it, and set the security version for projects to "2". Please refer to “12.5 Preventing Illegal Access to/Falsification of Data (Security Version)” in “Motion Control Setting Function Help” for details. For more information about the workaround, refer to the Mitsubishi Electric security advisory at "https://www.mitsubishielectric.com/psirt/vulnerability/pdf/2026-007_en.pdf". Mitigation For customers of the affected products, Mitsubishi Electric recommends using a computer with the affected product within a LAN and blocking remote logins from untrusted networks, hosts, and users, to minimize the risk of exploiting this vulnerability. Mitigation For customers of the affected products, Mitsubishi Electric recommends using a firewall, virtual private network (VPN), etc., to prevent unauthorized access, and allowing remote login only to trusted users when connecting a computer with the affected product to the Internet, to minimize the risk of exploiting this vulnerability. Mitigation For customers of the affected products, Mitsubishi Electric recommends preventing the user from clicking on web links contained in emails or other messages from untrusted sources, or from opening attachments in untrusted emails, to minimize the risk of exploiting this vulnerability. Mitigation For customers of the affected products, Mitsubishi Electric recommends installing antivirus software on a computer running the affected product, to minimize the risk of exploiting this vulnerability. Mitigation For customers of the affected products, Mitsubishi Electric recommends restricting physical access to a computer on which the affected product is installed, as well as to computers and network devices that can communicate with it, to minimize the risk of exploiting this vulnerability. Relevant CWE: CWE-303 Incorrect Implementation of Authentication Algorithm Metrics CVSS Version Base Score Base Severity Vector String 3.1 8.8 HIGH CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H 4.0 9.2 CRITICAL CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:H/SA:H Acknowledgments Mayeul Fargier, Erwan Cordier, Noé Flatreaud reported this vulnerability to Mitsubishi Electric. Legal Notice and Terms of Use This product is provided subject to this Notification (https://www.cisa.gov/notification) and this Privacy & Use policy (https://www.cisa.gov/privacy-policy). Recommended Practices CISA recommends users take defensive measures to minimize the exploitation risk of these vulnerabilities. Minimize network exposure for all control system devices and/or systems, and ensure they are not accessible from the internet. Locate control system networks and remote devices behind firewalls and isolate them from business networks. When remote access is required, use more secure methods, such as Virtual Private Networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most recent version available. Also recognize VPN is only as secure as its connected devices. CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures. CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies. CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets. Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov in the technical information paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies. Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents. Advisory Conversion Disclaimer This ICSA is a verbatim republication of Mitsubishi Electric 2026-007 from a direct conversion of the vendor's Common Security Advisory Framework (CSAF) advisory. This is republished to CISA's website as a means of increasing visibility and is provided "as-is" for informational purposes only. CISA is not responsible for the editorial or technical accuracy of republished advisories and provides no warranties of any kind regarding any information contained within this advisory. Further, CISA does not endorse any commercial product or service. Please contact Mitsubishi Electric directly for any questions regarding this advisory. Revision History Initial Release Date: 2026-09-17 Date Revision Summary 2026-09-17 1 Initial Publication 2026-09-17 2 Initial CISA Republication of Mitsubishi Electric 2026-007 advisory Legal Notice and Terms of Use