What is the CVSS score of CVE-2026-5434?

CVE-2026-5434 has a CVSS 3.1 base score of 5.9 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N. EPSS exploitation probability: 0.0%.

Is there a patch available for CVE-2026-5434?

Yes, a patch is available for CVE-2026-5434. Update the affected software to the latest version immediately.

Honeywell CNM CVE-2026-5434

EUVD-2026-31251 MEDIUM

Insertion of Sensitive Information into Externally-Accessible File (CWE-538)

2026-05-21 Honeywell

GHSA-m6f8-6m3m-x2rv

Information Disclosure Honeywell

5.9

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

5.9 MEDIUM

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

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

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

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

Lifecycle Timeline

Analysis Generated

May 21, 2026 - 09:34 vuln.today

DescriptionCVE.org

Honeywell Control Network Module (CNM) contains insertion of sensitive information into an unintended directory. An attacker could exploit this vulnerability through probing system files, potentially resulting in unintended access to protected data.

AnalysisAI

Sensitive information disclosure in Honeywell Control Network Module (CNM) versions 100.1 through 110.2 allows unauthenticated remote attackers to access protected data by probing system file paths that inadvertently receive sensitive writes. The root cause is CWE-538, where the module incorrectly routes sensitive information into directories accessible outside the intended trust boundary. No public exploit code has been identified at time of analysis, and this vulnerability is not listed in the CISA KEV catalog; however, its presence in an industrial control system network component elevates the operational consequence of any successful confidentiality breach.

Technical ContextAI

CWE-538 (Insertion of Sensitive Information into Externally-Accessible File or Directory) describes a class of flaws where an application writes data - such as credentials, session tokens, cryptographic material, or configuration secrets - to a filesystem location that is readable by parties outside the intended access scope. The affected component, Honeywell's Control Network Module (CNM), is an industrial automation network interface product identified by CPE cpe:2.3:a:honeywell_international_inc.:control_network_module_(cnm):*:*:*:*:*:*:*:*. In OT/ICS deployments, CNM devices typically bridge process control networks and enterprise or supervisory layers, making any unintended file exposure on such a device particularly sensitive - the data written could include network credentials, configuration parameters, or inter-device authentication material used across the control network.

RemediationAI

A vendor-released patch is confirmed available from Honeywell; operators should consult the Honeywell Process Solutions advisory portal at https://process.honeywell.com/ to obtain the specific patched firmware or software version applicable to their CNM deployment. The exact fixed version number was not independently specified in the available advisory data beyond the vendor confirmation, so administrators should verify the target version directly with Honeywell support before deployment. As a compensating control while patching is scheduled, restrict network-layer access to the CNM management interface using firewall rules or network segmentation to limit which hosts can reach the device's file-accessible interfaces - reducing the pool of potential attackers given the AC:H requirement. Additionally, audit filesystem permissions on CNM-accessible directories and review any logging or diagnostic features that may contribute to sensitive data being written to unexpected paths. Note that network restriction does not eliminate the vulnerability but raises the bar for exploitation given the already-elevated attack complexity.