CVE-2025-43873
highpriority · track · 0EPSS 0.003 · 21 %ileEUUSEPSS · scored 2026-10-27
Successful exploitation of these vulnerabilities could allow an attacker to modify firmware and gain full access to the device.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixediSTAR Edge G2cisa_csaf_ot
Upgrade iSTAR Ultra G2, iSTAR Ultra G2 SE, iSTAR Edge G2 to version 6.9.3 or greater.
- FixediSTAR Ultracisa_csaf_ot
Upgrade iSTAR Ultra, iSTAR Ultra SE, iSTAR Ultra LT to version 6.9.7.CU01 or greater.
- FixediSTAR Ultra G2cisa_csaf_ot
Upgrade iSTAR Ultra G2, iSTAR Ultra G2 SE, iSTAR Edge G2 to version 6.9.3 or greater.
- FixediSTAR Ultra G2 SEcisa_csaf_ot
Upgrade iSTAR Ultra G2, iSTAR Ultra G2 SE, iSTAR Edge G2 to version 6.9.3 or greater.
- FixediSTAR Ultra LTcisa_csaf_ot
Upgrade iSTAR Ultra, iSTAR Ultra SE, iSTAR Ultra LT to version 6.9.7.CU01 or greater.
- FixediSTAR Ultra SEcisa_csaf_ot
Upgrade iSTAR Ultra, iSTAR Ultra SE, iSTAR Ultra LT to version 6.9.7.CU01 or greater.
- MitigationiSTAR Edge G2cisa_csaf_ot
Johnson Controls recommends taking steps to minimize risks to all building automation systems in alignment with CISA's guidance.
- MitigationiSTAR Ultracisa_csaf_ot
Johnson Controls recommends taking steps to minimize risks to all building automation systems in alignment with CISA's guidance.
- MitigationiSTAR Ultra G2cisa_csaf_ot
Johnson Controls recommends taking steps to minimize risks to all building automation systems in alignment with CISA's guidance.
- MitigationiSTAR Ultra G2 SEcisa_csaf_ot
Johnson Controls recommends taking steps to minimize risks to all building automation systems in alignment with CISA's guidance.
- MitigationiSTAR Ultra LTcisa_csaf_ot
Johnson Controls recommends taking steps to minimize risks to all building automation systems in alignment with CISA's guidance.
- MitigationiSTAR Ultra SEcisa_csaf_ot
Johnson Controls recommends taking steps to minimize risks to all building automation systems in alignment with CISA's guidance.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.3–8.8
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (13)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- ICSA-25-345-02Johnson Controls iSTAR Ultra2025-12-11icsa · cisa_csaf_otUS
Successful exploitation of these vulnerabilities could allow an attacker to modify firmware and gain full access to the device.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6)
External citations — patches, advisories, analysis.
- https://www.cisa.gov/news-events/ics-advisories/icsa-25-345-02cnnvd
- https://www.johnsoncontrols.com/trust-center/cybersecurity/security-advisoriescnnvd
- https://www.cisa.gov/news-events/ics-advisories/icsa-25-345-02enisa_euvd
- https://www.johnsoncontrols.com/trust-center/cybersecurity/security-advisoriesenisa_euvd
- https://www.cisa.gov/news-events/ics-advisories/icsa-25-345-02nvd
- https://www.johnsoncontrols.com/trust-center/cybersecurity/security-advisoriesnvd
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