CVE-2026-21656

Name: CVE-2026-21656
Creator: NVD / NIST
Published: 2026-02-27T09:16:16.417+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 0.39%

Last modified Jun 17, 2026

CVE-2026-21656 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. 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 of the device before authentication occurs.This issue affects Frick Controls Quantum HD version 10.22 and prior.. EPSS estimates a 0.39% chance of exploitation in the next 30 days.

Description

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

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS 4.0

8.8/10

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/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 Probability

0.39%

31.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-94

Affected Software

Vendor	Product	Versions
Johnsoncontrols	Frick Controls Quantum Hd Firmware	<= 10.22

References

https://www.cisa.gov/news-events/ics-advisories/icsa-26-057-01Third Party Advisory, US Government Resource
https://www.johnsoncontrols.com/trust-center/cybersecurity/security-advisoriesVendor Advisory

Timeline

Published: Feb 27, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-21656?

How severe is CVE-2026-21656?

CVE-2026-21656 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 0.39% probability of exploitation in the next 30 days.

How do I fix CVE-2026-21656?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-21656?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST