CVE-2026-21661

AC2000 Uncontrolled Search Path Element

Published: May 6, 2026Updated: Aug 24, 2026 Sources: CVE List NVD csafCWE-427

8.7HIGH

Description

An Uncontrolled Search Path Element vulnerability in JohnsonControls AC2000 on Windows allows Leveraging/Manipulating Configuration File Search Paths. This issue affects AC2000: from 10.6 before release 10, from 11.0 before release 9, from 12 before release 3.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:LAttack Vector

Local

AC:LAttack Complexity

Low

PR:LPrivileges Required

Low

UI:NUser Interaction

None

Scope

S:CScope

Changed

Impact

C:HConfidentiality

High

I:HIntegrity

High

A:LAvailability

Low

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Weaknesses

CWE-427

Affected Products

Johnson Controls

commercial·USaka exacqvision, metasys, jci, frick controls quantum hd

AC2000On-prem

ICS / OT / IoT / building-automation

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Persistence

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References

https://www.johnsoncontrols.com/trust-center/cybersecurity/security-advisories

johnsoncontrols.com

https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/OT/white/2026/icsa-26-125-05.json

raw.githubusercontent.com

https://www.cisa.gov/news-events/ics-advisories/icsa-26-125-05

cisa.gov

and 15 more references View all →

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