ICSA-26-279-06: Hitachi Energy RTU500

CISA's summary

Summary: Hitachi Energy is publishing this cybersecurity advisory in response to the security findings reported by Dragos affecting end-of-life RTU500 CMU firmware version 9.x. The reported findings are associated with legacy RTU500 firmware versions that were developed according to the cybersecurity requirements, threat landscape, and industry practices that existed at the time of their release. As cybersecurity threats and security expectations have evolved, these end-of-life versions no longer incorporate many of the security controls and hardening measures that are standard in modern industrial control systems. Over successive RTU500 releases, Hitachi Energy has continuously enhanced the security of the product through the introduction of additional security features, protocol hardening, stronger authentication and access controls, encrypted communications, and other security-by-design improvements. While the findings reported by Dragos do not affect currently supported RTU500 CMU firmware versions, there is a likelihood that the end-of-life versions 11.x and prior are affected by these vulnerabilities. Since the end-of-life versions are no longer maintained with security updates, Hitachi Energy strongly recommends upgrading to a currently supported RTU500 firmware version. Customers should also implement appropriate defense-in-depth measures and cybersecurity best practices to reduce risk and strengthen the security posture of their operational environments. Please refer to the Recommended Immediate Actions for information about the mitigation/remediation.

Products, as the advisory lists them

DeSpy has not checked any unit, hardware revision or firmware.

Vulnerabilities in this advisory

• CVE-2026-8065 — CVE-2026-8065 · CWE-306

  An authentication bypass vulnerability in the firmware update endpoint of Hitachi Energy RTU500 allows an unauthenticated attacker to upload arbitrary firmware through a crafted POST request. Successful exploitation could allow the attacker to modify device functionality or compromise the integrity or availability of the device.

• CVE-2026-8066 — CVE-2026-8066 · CWE-23

  A directory traversal vulnerability in the file upload functionality of Hitachi Energy RTU500 allows an unauthenticated attacker to write or overwrite arbitrary files on the device file system. Depending on the files affected, successful exploitation could result in unauthorized modification of device data or disruption of the device’s intended operation.

• CVE-2026-8067 — CVE-2026-8067 · CWE-862

  An improper authorization vulnerability in the RTU500’s web application allows an authenticated user to trigger the RTU500 to reboot through the reset endpoint. Successful exploitation could cause temporary device unavailability and disruption of its intended operation.

• CVE-2010-2965 — CVE-2010-2965 · CWE-863

  The WDB target agent debug service in Wind River VxWorks 6.x, 5.x, and earlier, as used on few of the Hitachi Energy RTU500 CMU firmware legacy versions, allows remote attackers to read or modify arbitrary memory locations, perform function calls, or manage tasks via requests to UDP port 17185.

• CVE-2014-9195 — CVE-2014-9195 · CWE-306

  Missing authentication vulnerability in a network service of Hitachi Energy RTU500 allows an unauthenticated remote attacker to execute arbitrary commands using protocol-compliant network traffic. Successful exploitation could result in unauthorized modification of the device or disruption of its intended operation.

• CVE-2023-46143 — CVE-2023-46143 · CWE-494

  A download of code without integrity check vulnerability in Hitachi Energy RTU500 allows an unauthenticated remote attacker to modify some or all applications running on the device. Successful exploitation could result in unauthorized modification of device functionality or disruption of its intended operation.

Acknowledgments, as the advisory lists them

• Dragos

The advisory's legal notice

The information in this document is subject to change without notice and should not be construed as a commitment by Hitachi Energy. Hitachi Energy provides no warranty, express or implied, including warranties of merchantability and fitness for a particular purpose, for the information contained in this document, and assumes no responsibility for any errors that may appear in this document. In no event shall Hitachi Energy or any of its suppliers be liable for direct, indirect, special, incidental or consequential damages of any nature or kind arising from the use of this document, or from the use of any hardware or software described in this document, even if Hitachi Energy or its suppliers have been advised of the possibility of such damages. This document and parts hereof must not be reproduced or copied without written permission from Hitachi Energy and the contents hereof must not be imparted to a third party nor used for any unauthorized purpose. All rights to registrations and trademarks reside with their respective owners.

Sources

• The advisory at cisa.gov
• The CSAF document (JSON)

DeSpy's copy of this version is dated 2026-10-06.