Cyber Resilience

CVE-2026-21661

High

Published: 06 May 2026

Published
06 May 2026
Modified
06 May 2026
KEV Added
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Patch
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CVSS Score v4 8.4 CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0011 1.4th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-21661 is a high-severity Uncontrolled Search Path Element (CWE-427) vulnerability in Johnsoncontrols (inferred from references). Its CVSS base score is 8.4 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Path Interception by Search Order Hijacking (T1574.008); ranked at the 1.4th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

A08:2025 Software or Data Integrity Failures

EU & UK References

Vulnerability details

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.

CWE(s)
CWE-427

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1574.008 Path Interception by Search Order Hijacking Stealth
Adversaries may execute their own malicious payloads by hijacking the search order used to load other programs.
attack.mitre.org →
Why these techniques?

CWE-427 uncontrolled search path directly enables search order hijacking for malicious file loading.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

Affected Assets

Johnsoncontrols
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inferred from references and description; NVD did not file a CPE for this CVE

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References