View CSAF

1. EXECUTIVE SUMMARY

• CVSS v4 8.7
• ATTENTION: Exploitable remotely/low attack complexity
• Vendor: Johnson Controls Inc.
• Equipment: iSTAR Ultra, iSTAR Ultra SE, iSTAR Ultra G2, iSTAR Ultra G2 SE, iSTAR Edge G2
• Vulnerabilities: Improper Neutralization of Special Elements used in an OS Command

2. RISK EVALUATION

Successful exploitation of these vulnerabilities could result in unauthorized access to the device.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

Johnson Controls reports the following products are affected:

• iSTAR Ultra: Versions prior to 6.9.7.CU01
• iSTAR Ultra SE: Versions prior to 6.9.7.CU01
• iSTAR Ultra G2: Versions prior to 6.9.3
• iSTAR Ultra G2 SE: Versions prior to 6.9.3
• iSTAR Edge G2: Versions prior to 6.9.3

3.2 VULNERABILITY OVERVIEW

3.2.1 Improper Neutralization of Special Elements used in an OS Command CWE-78

Under certain circumstances a successful exploitation of this vulnerability could result in access to the device.

CVE-2025-43875 has been assigned to this vulnerability. A CVSS v3.1 base score of 8.8 has been calculated; the CVSS vector string is (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).

A CVSS v4 score has also been calculated for CVE-2025-43875. A base score of 8.7 has been calculated; the CVSS vector string is (CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N).

3.2.2 Improper Neutralization of Special Elements used in an OS Command CWE-78

Under certain circumstances a successful exploitation of this vulnerability could result in access to the device.

CVE-2025-43876 has been assigned to this vulnerability. A CVSS v3.1 base score of 8.8 has been calculated; the CVSS vector string is (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).

A CVSS v4 score has also been calculated for CVE-2025-43876. A base score of 8.7 has been calculated; the CVSS vector string is (CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N).

3.3 BACKGROUND

• CRITICAL INFRASTRUCTURE SECTORS: Commercial Facilities, Critical Manufacturing, Energy, Government Facilities, Transportation Systems
• COUNTRIES/AREAS DEPLOYED: Worldwide
• COMPANY HEADQUARTERS LOCATION: Ireland

3.4 RESEARCHER

Johnson Controls reported these vulnerabilities to CISA.

4. MITIGATIONS

Johnson Controls recommends users complete the following actions to address these issues:

• Upgrade iSTAR Ultra, and iSTAR Ultra SE to version 6.9.7.CU01 or greater.
• Upgrade iSTAR Ultra G2, iSTAR Ultra G2 SE, and iSTAR Edge G2 to version 6.9.3 or greater.

For detailed mitigation instructions, see the Johnson Controls Product Security Advisories JCI-PSA-2025-14 and JCI-PSA-2025-15. Johnson Controls recommends implementing measures to minimize risks to all building automation systems.

Further ICS security notices and product security guidance are located at the Johnson Controls product security website.

Contact Johnson Controls Global Product Security.

CISA recommends users take defensive measures to minimize the risk of exploitation of these vulnerabilities, such as:

• Minimize network exposure for all control system devices and/or systems, ensuring they are not accessible from the Internet.
• Locate control system networks and remote devices behind firewalls and isolating 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 current version available. Also recognize VPN is only as secure as the 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/ics. 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/ics 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.

CISA also recommends users take the following measures to protect themselves from social engineering attacks:

• Do not click web links or open attachments in unsolicited email messages.
• Refer to Recognizing and Avoiding Email Scams for more information on avoiding email scams.
• Refer to Avoiding Social Engineering and Phishing Attacks for more information on social engineering attacks.

No known public exploitation specifically targeting these vulnerabilities has been reported to CISA at this time.

5. UPDATE HISTORY

• December 11, 2025: Initial Republication of Johnson Controls JCI-PSA-2025-14 and JCI-PSA-2025-15.