VulnerabilityPublished 17 Dec 2025

CVE-2025-61736: Johnson Controls iSTAReX, iSTAR Edge, iSTAR Ultra LT, iSTAR Ultra , iSTAR Ultra SE · -Improper Validation of certificate expiration

Affects Johnson Controls iSTAReX, iSTAR Edge, iSTAR Ultra LT, iSTAR Ultra , iSTAR Ultra SESource CVE Database V5

Not known to be exploited · CVSS 7.1 High : upgrade to 1.2 soon.

Data as of 26 Oct 2026, 10:12 UTC

CVSS 4.0 base score

7.1High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.1% chance of exploitation in 30 days – higher than 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 1.2

CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Attack Vector: Adjacent
Attack Complexity: Low
Attack Requirements: None
Privileges Required: None
User Interaction: None
Vulnerable system confidentiality: None
Vulnerable system integrity: None
Vulnerable system availability: High
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Adjacent: The vulnerable system is bound to a protocol stack, but the attack is limited at the protocol level to a logically adjacent topology. This can mean an attack must be launched from the same shared proximity (e.g., Bluetooth, NFC, or IEEE 802.11) or logical network (e.g., local IP subnet), or from within a secure or otherwise limited administrative domain (e.g., MPLS, secure VPN within an administrative network zone).
Attack Complexity: Low: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without interaction from any human user, other than the attacker.
Vulnerable system confidentiality: None: There is no loss of confidentiality within the Vulnerable System.
Vulnerable system integrity: None: There is no loss of integrity within the Vulnerable System.
Vulnerable system availability: High: There is a total loss of availability, resulting in the attacker being able to fully deny access to resources in the Vulnerable System; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the Vulnerable System (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 17 Dec 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade Johnson Controls iSTAReX, iSTAR Edge, iSTAR Ultra LT, iSTAR Ultra , iSTAR Ultra SE to 1.2.

Affected software

Product	Affected	Fixed in
Johnson Controls iSTAReX, iSTAR Edge, iSTAR Ultra LT, iSTAR Ultra , iSTAR Ultra SE	Affected <1.2	Fixed in 1.2

AI-suggested

Upgrade affected Johnson Controls iSTAR devices to firmware versions that support TLS 1.2 or later, as these versions are expected to include proper certificate expiration validation.
Implement a certificate lifecycle management process that tracks certificate expiration dates well in advance to allow timely renewal or replacement.
Where immediate upgrades are not feasible, establish manual monitoring and intervention procedures to restore communication if devices fail post-certificate expiration.
Deploy redundant communication channels or failover mechanisms to maintain security system availability during outages caused by this vulnerability.
Conduct regular security audits and penetration tests focusing on physical security infrastructure to detect potential disruptions.
Coordinate with Johnson Controls support for any interim patches or workarounds that may be available.
Integrate alerting systems to notify administrators of impending certificate expirations and communication failures.
Review and update incident response plans to include scenarios involving physical security system communication failures.
Limit network access to these devices to trusted segments to reduce exposure to potential exploitation attempts.
Document and train relevant personnel on the vulnerability and mitigation steps to ensure preparedness.

Description

Successful exploitation of this vulnerability could result in the product failing to re-establish communication once the certificate expires.

Impact

For European organizations, the impact of CVE-2025-61736 is primarily operational, affecting the availability of physical security systems that utilize Johnson Controls iSTAR products. Disruption in communication can lead to failure in access control, alarm monitoring, and other security functions, potentially exposing facilities to unauthorized access or delayed incident response. Critical infrastructure sectors such as transportation hubs, government buildings, healthcare facilities, and industrial plants that rely on these devices could face increased security risks and operational downtime. The inability to re-establish communication after certificate expiration may also complicate incident management and recovery efforts. Moreover, organizations may face compliance challenges with security regulations requiring continuous monitoring and control of physical access. Given the vulnerability does not allow for data exfiltration or privilege escalation, the confidentiality and integrity impacts are limited, but the availability impact is significant. The lack of known exploits reduces immediate risk but does not eliminate the threat, especially as attackers may develop exploits targeting this flaw. European entities with large-scale deployments of Johnson Controls security systems should consider this vulnerability a high priority for remediation to avoid service interruptions.

CWE-298Improper Validation of Certificate Expiration (opens in a new tab)
Variant weaknessLikelihood of exploit: LowOWASP Top 10 A07:2025: Authentication Failures (opens in a new tab)
A certificate expiration is not validated or is incorrectly validated.
Architecture and Design
Check for expired certificates and provide the user with adequate information about the nature of the problem and how to proceed.
Implementation
If certificate pinning is being used, ensure that all relevant properties of the certificate are fully validated before the certificate is pinned, including the expiration.
OWASP Cheat Sheets
OWASP Authentication (opens in a new tab)
OWASP ASVS 4.0.3
V2.8.5 (opens in a new tab)
V2.8.4 (opens in a new tab)
V9.2.3 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 24 Dec 2025, 13:16 UTC

WeaknessesCWE-298

Technical details

References

Community reviews

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