1. EXECUTIVE SUMMARY
- CVSS v3 5.9
- ATTENTION: Exploitable remotely
- Vendor: Hitachi Energy
- Equipment: RTU500 series CMU
- Vulnerability: Buffer Copy without Checking Size of Input (‘Classic Buffer Overflow’)
2. RISK EVALUATION
Successful exploitation of this vulnerability could allow an attacker to cause a denial-of-service condition.
3. TECHNICAL DETAILS
3.1 AFFECTED PRODUCTS
The following Hitachi Energy products are affected:
- RTU500 series CMU Firmware: Versions 12.0.1 through 12.0.14
- RTU500 series CMU Firmware: Versions 12.2.1 through 12.2.11
- RTU500 series CMU Firmware: Versions 12.4.1 through 12.4.11
- RTU500 series CMU Firmware: Versions 12.6.1 through 12.6.9
- RTU500 series CMU Firmware: Versions 12.7.1 through 12.7.6
- RTU500 series CMU Firmware: Versions 13.2.1 through 13.2.6
- RTU500 series CMU Firmware: Versions 13.4.1 through 13.4.3
- RTU500 series CMU Firmware: Version 13.5.1
3.2 Vulnerability Overview
3.2.1 Buffer Copy without Checking Size of Input (‘Classic Buffer Overflow’) CWE-120
A vulnerability exists in SCI IEC 60870-5-104 and HCI IEC 60870-5-104 that affects the RTU500 series product. Specially crafted messages sent to the mentioned components are not validated properly and can result in buffer overflow and as final consequence to a reboot of an RTU500 CMU.
CVE-2023-6711 has been assigned to this vulnerability. A CVSS v3 base score of 5.9 has been assigned; the CVSS vector string is (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H).
3.3 BACKGROUND
- CRITICAL INFRASTRUCTURE SECTORS: Energy
- COUNTRIES/AREAS DEPLOYED: Worldwide
- COMPANY HEADQUARTERS LOCATION: Switzerland
3.4 RESEARCHER
Toralf Gimpel from GAI NetConsult GmbH reported this vulnerability to Hitachi Energy.
4. MITIGATIONS
Hitachi Energy recommends that users update to the respective series CMU firmware version as below.
- Hitachi Energy RTU500 series CMU Firmware 12.0.15
- Hitachi Energy RTU500 series CMU Firmware 12.2.12
- Hitachi Energy RTU500 series CMU Firmware 12.4.12
- Hitachi Energy RTU500 series CMU Firmware 12.6.10
- Hitachi Energy RTU500 series CMU Firmware 12.7.7
- Hitachi Energy RTU500 series CMU Firmware 13.2.7
- Hitachi Energy RTU500 series CMU Firmware 13.4.4
- Hitachi Energy RTU500 series CMU Firmware 13.5.2
Hitachi Energy recommends that users follow the “Remote Terminal Units Security Deployment Guideline” as well to apply mitigation as described below.
Hitachi Energy recommends users implementing recommended security practices and firewall configurations to help protect the process control network from attacks originating from outside the network. Process control systems should be physically protected from direct access by unauthorized personnel, have no direct connections to the Internet, and be separated from other networks by means of a firewall system with a minimal number of ports exposed. Process control systems should not be used for Internet surfing, instant messaging, or receiving e-mails. Portable computers and removable storage media should be carefully scanned for viruses before they are connected to a control system.
For more information, see Hitachi Energy Cybersecurity Advisory “DoS Vulnerability in Hitachi Energy’s RTU500 series products”.
For additional information and support please contact your product provider or Hitachi Energy service organization at https://www.hitachienergy.com/contact-us/.
CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. 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.
No known public exploitation specifically targeting this vulnerability has been reported to CISA at this time. This vulnerability has a high attack complexity.
5. UPDATE HISTORY
- December 19, 2024: Initial Publication