Is CVE-2026-13742 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-13742 being exploited in the wild.

How severe is CVE-2026-13742?

Informational severity, with a CVSS score of 5.9, published 29 June 2026.

Which products and versions are affected?

Honeywell IQ MultiAccess All versions prior to and including version 28.

Is there a fix for CVE-2026-13742?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-13742 attacked?

It is attacked with local access, in a network appliance.

Am I affected by CVE-2026-13742?

Check whether you run Honeywell IQ MultiAccess at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-13742: Honeywell IQ MultiAccess improper signature verification via TOCTOU

CVE-2026-13742 · Severity: info · CVSS 5.9 · Published 2026-06-29

Honeywell IQ MultiAccess, a professional access control system used for managing building security and personnel entry, is affected by a vulnerability in how it verifies file signatures. An attacker with local access to the system could exploit a timing-based flaw to replace legitimate software files with malicious ones during the download process. This could allow an attacker to compromise the security system's integrity, potentially leading to unauthorized access or operational disruptions.

Vendors: Honeywell.

Quick answers

Is CVE-2026-13742 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-13742 being exploited in the wild.
How severe is CVE-2026-13742?: Informational severity, with a CVSS score of 5.9, published 29 June 2026.
Which products and versions are affected?: Honeywell IQ MultiAccess All versions prior to and including version 28.
Is there a fix for CVE-2026-13742?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-13742 attacked?: It is attacked with local access, in a network appliance.
Am I affected by CVE-2026-13742?: Check whether you run Honeywell IQ MultiAccess at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

Honeywell IQ MultiAccess (up to version 28) is vulnerable to a Time-of-Check Time-of-Use (TOCTOU) race condition (CWE-367) during the digital signature verification process for downloaded files. An attacker with local, low-privileged access can exploit the window between the file's verification and its execution/installation to replace the legitimate file with a malicious payload. This bypasses the integrity checks intended to ensure only authentic Honeywell software is run. Honeywell recommends upgrading to V27 SP1 or V28 SP1 to mitigate this issue.

Affected products

Honeywell IQ MultiAccess All versions prior to and including version 28

Timeline

2026-06-29: disclosed
2026-06-29: advisory

References

https://www.honeywell.com/us/en/product-security

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