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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-3611 Detail

Description

The Honeywell IQ4x building management controller, exposes its full web-based HMI without authentication in its factory-default configuration. With no user module configured, security is disabled by design and the system operates under a System Guest (level 100) context, granting read/write privileges to any party able to reach the HTTP interface. Authentication controls are only enforced after a web user is created via U.htm, which dynamically enables the user module. Because this function is accessible prior to authentication, a remote user can create a new account with administrative read/write permissions enabling the user module and imposing authentication under attacker-controlled credentials. This action can effectively lock legitimate operators out of local and web-based configuration and administration.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  ICS-CERT
CVSS-B 10.0 CRITICAL
Vector:  CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-069-03.json ICS-CERT
https://www.cisa.gov/news-events/ics-advisories/icsa-26-069-03 ICS-CERT
https://www.honeywell.com/us/en/contact ICS-CERT

Weakness Enumeration

CWE-ID CWE Name Source
CWE-306 Missing Authentication for Critical Function ICS-CERT  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-3611
NVD Published Date:
03/12/2026
NVD Last Modified:
03/13/2026
Source:
ICS-CERT