Back to CVE records
Critical 10.0Published Mar 12, 2026

CVE-2026-3611The Honeywell IQ4x building management controller, exposes its full web-based HMI without authentication in its factory-default configuration.

Updated under an hour ago ()

Does this affect you?

It affects honeywell iq4e_firmware and 4 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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.

CVSS
10.0 CRITICAL (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Weakness (CWE)
CWE-306
Known exploited
Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days)
Not loaded for this CVE
Assigned by
Not given
NVD analysis
Analyzed
Record last updated
Jun 17, 2026
First seen by InfoSec Signals
Oct 9, 2026

Affected products

Affected products
honeywell iq4e_firmware
honeywell:iq4e_firmware
before 3.30
NVD
honeywell iq412_firmware
honeywell:iq412_firmware
before 3.30
NVD
honeywell iq422_firmware
honeywell:iq422_firmware
before 3.30
NVD
honeywell iq4nc_firmware
honeywell:iq4nc_firmware
before 3.30
NVD
honeywell iq41x_firmware
honeywell:iq41x_firmware
before 3.30
NVD

References

  • issue-tracking
  • third-party-advisory, us-government-resource
  • product

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.

Your cookie choices
We use essential cookies to run this site, and, only with your consent, an advertising cookie from Google to measure whether our ads lead to sign-ups and subscriptions. See our for details.