JohnsonControls AC2000 on Windows Configuration File uncontrolled search path

CVSS Meta Temp Score
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CTI Interest Score
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6.7$0-$5k0.00

Summaryinfo

A vulnerability categorized as problematic has been discovered in JohnsonControls AC2000 on Windows. This affects an unknown part of the component Configuration File Handler. The manipulation results in uncontrolled search path. This vulnerability is reported as CVE-2026-21661. The attack requires a local approach. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in JohnsonControls AC2000 on Windows (affected version unknown). It has been classified as critical. Affected is an unknown functionality of the component Configuration File Handler. The manipulation with an unknown input leads to a uncontrolled search path vulnerability. CWE is classifying the issue as CWE-427. The product uses a fixed or controlled search path to find resources, but one or more locations in that path can be under the control of unintended actors. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is shared for download at johnsoncontrols.com. This vulnerability is traded as CVE-2026-21661 since 01/02/2026. The exploitability is told to be difficult. The attack needs to be approached locally. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1574.

Upgrading eliminates this vulnerability.

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Productinfo

Vendor

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 7.0
VulDB Meta Temp Score: 6.7

VulDB Base Score: 7.0
VulDB Temp Score: 6.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Uncontrolled search path
CWE: CWE-427 / CWE-426
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Timelineinfo

01/02/2026 CVE reserved
05/06/2026 +123 days Advisory disclosed
05/06/2026 +0 days VulDB entry created
05/06/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: johnsoncontrols.com
Status: Confirmed

CVE: CVE-2026-21661 (🔒)
GCVE (CVE): GCVE-0-2026-21661
GCVE (VulDB): GCVE-100-361572

Entryinfo

Created: 05/06/2026 19:01
Changes: 05/06/2026 19:01 (66)
Complete: 🔍
Cache ID: 216::103

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