CVE-2025-43873: iSTAR Ultra, Ultra SE, Ultra G2, Ultra G2 SE, iSTAR Edge G2 - Authenticated web application command injection - setFaultDebounce

Published Dec 17, 2025
·
Updated

Successful exploitation of these vulnerabilities could allow an attacker to modify firmware and gain full access to the device.

Affected Software

6 affected componentsFixes available
: Johnson Controls iSTAR Ultra: Versions prior to 6.9.7.CU01
: Johnson Controls iSTAR Ultra SE: Versions prior to 6.9.7.CU01
: Johnson Controls iSTAR Ultra LT: Versions prior to 6.9.7.CU01
: Johnson Controls iSTAR Ultra G2<6.9.3
6.9.3
: Johnson Controls iSTAR Ultra G2 SE<6.9.3
6.9.3
: Johnson Controls iSTAR Edge G2<6.9.3
6.9.3

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 6.9.3
  2. Upgrade

    Upgrade iSTAR Ultra G2, iSTAR Ultra G2 SE, iSTAR Edge G2 to a version that resolves this vulnerability.

    Fixed in 6.9.3
  3. Upgrade

    Upgrade iSTAR Ultra, iSTAR Ultra SE, iStar Ultra LT to a version that resolves this vulnerability.

    Fixed in 6.9.7.CU01

Event History

Dec 17, 2025
CVE Published
via MITRE·03:53 PM
Data Sourced
via MITRE·03:53 PM
RemedyDescriptionWeakness
Data Sourced
via ICS·04:01 PM
SeverityWeaknessAffected Software
Data Sourced
via NVD·04:16 PM
DescriptionSeverityWeakness

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2025-43873?

CVE-2025-43873 has a high severity rating due to the potential for firmware modification and complete device access.

2

How do I fix CVE-2025-43873?

To mitigate CVE-2025-43873, update the affected Johnson Controls iSTAR devices to versions 6.9.7.CU01 or later.

3

Which products are affected by CVE-2025-43873?

CVE-2025-43873 affects Johnson Controls iSTAR Ultra, iSTAR Ultra SE, and iSTAR Ultra LT prior to version 6.9.7.CU01.

4

What can attackers do if they exploit CVE-2025-43873?

Successful exploitation of CVE-2025-43873 allows attackers to modify firmware and gain full access to the affected device.

5

Is there a specific version that resolves CVE-2025-43873 for the iSTAR Ultra G2?

Yes, updating the iSTAR Ultra G2 to version 6.9.3 resolves the vulnerabilities identified in CVE-2025-43873.

Company

Resources

Contact

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