Cyber Posture

CVE-2026-21658

Critical

Published: 27 February 2026

Published
27 February 2026
Modified
02 March 2026
KEV Added
Patch
CVSS Score 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0037 59.1th percentile
Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Description

Unauthenticated Remote Code Execution i.e Improper Control of Generation of Code ('Code Injection') vulnerability in Johnson Controls Frick Controls Quantum HD allows Code Injection. Insufficient validation of input in certain parameters may permit unexpected actions, which could impact the security…

more

of the device before authentication occurs.This issue affects Frick Controls Quantum HD version 10.22 and prior.

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly mitigates the code injection vulnerability by requiring comprehensive input validation at affected parameters to prevent unexpected code execution.

prevent

Ensures timely patching and remediation of the specific unauthenticated RCE flaw in Quantum HD version 10.22 and prior, as outlined in vendor advisories.

prevent

Limits and documents permitted unauthenticated actions to prohibit those enabling code injection and security impacts prior to authentication.

Security SummaryAI

CVE-2026-21658 is an unauthenticated remote code execution vulnerability stemming from improper control of code generation, classified as a code injection issue (CWE-94), in Johnson Controls Frick Controls Quantum HD. The flaw arises from insufficient validation of input in certain parameters, enabling unexpected actions that compromise device security prior to authentication. It affects Quantum HD version 10.22 and prior versions, earning a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

Attackers require no privileges or user interaction and can exploit the vulnerability remotely over the network with low complexity. Successful exploitation grants full remote code execution, potentially allowing high-impact disruption to confidentiality, integrity, and availability of the affected device.

Mitigation details are outlined in the CISA ICS advisory ICSA-26-057-01 and Johnson Controls security advisories, available at the respective reference URLs. Security practitioners should consult these for patching instructions and workarounds.

Details

CWE(s)

Affected Products

johnsoncontrols
frick controls quantum hd firmware
≤ 10.22

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

The vulnerability is an unauthenticated remote code execution in a network-accessible industrial control system device via code injection in parameters, directly enabling exploitation of a public-facing application.

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

References