CVE-2026-33389

Disabled and non-configurable certificate/host key validation in Smart Polling in Guardian/CMC before 26.3.0 and Arc before v2.7.0

Published Sep 8, 2026 CVSS 4.0 · 5.3 Medium EPSS < 1% KEV · Not listed
Description
An improper certificate/host key validation vulnerability was discovered in the Smart Polling functionality, which established encrypted connections to target devices without validating the remote host's identity, and no option was provided to enable it. A man-in-the-middle attacker positioned between a sensor and a polled device can, during a polling session, impersonate the device and intercept the communication, including the credentials used to access it. The captured credentials can then be replayed to authenticate against the device itself or against other devices sharing the same credentials, allowing the attacker to access and tamper with the device's data and to disrupt its operations.

Remediation

Vendor Solution

Upgrade Guardian/CMC to v26.3.0 or later. Upgrade Arc to v2.7.0 or later.

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description An improper certificate/host key validation vulnerability was discovered in the Smart Polling functionality, which established encrypted connections to target devices without validating the remote host's identity, and no option was provided to enable it. A man-in-the-middle attacker positioned between a sensor and a polled device can, during a polling session, impersonate the device and intercept the communication, including the credentials used to access it. The captured credentials can then be replayed to authenticate against the device itself or against other devices sharing the same credentials, allowing the attacker to access and tamper with the device's data and to disrupt its operations.
Title Disabled and non-configurable certificate/host key validation in Smart Polling in Guardian/CMC before 26.3.0 and Arc before v2.7.0
First Time appeared Nozomi Networks
Nozomi Networks arc
Nozomi Networks cmc
Nozomi Networks guardian
Weaknesses CWE-671
CPEs cpe:2.3:a:nozomi_networks:arc:*:*:*:*:*:*:*:*
cpe:2.3:a:nozomi_networks:cmc:*:*:*:*:*:*:*:*
cpe:2.3:a:nozomi_networks:guardian:*:*:*:*:*:*:*:*
Vendors & Products Nozomi Networks
Nozomi Networks arc
Nozomi Networks cmc
Nozomi Networks guardian
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:L'}

cvssV4_0

{'score': 5.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:L/SA:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
Nozomi
Published
Updated
Oct 15, 2026, 1:18 AM
Reserved
Mar 19, 2026, 11:28 AM
Status
Awaiting Analysis
Published
Sep 8, 2026, 2:17 PM
Modified
Oct 15, 2026, 2:19 AM