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 · corrected/updated Oct 15, 2026 · Nozomi Networks · evidence confidence high
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.
Grounded briefings
Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.
Executive
CVE-2026-33389 is a high public vulnerability record for Nozomi Networks. It is not currently listed in the CISA Known Exploited catalog. Check the linked vendor or CERT advisories for patch status. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.
System administrator
Identify whether Nozomi Networks is in your estate, then compare installed versions with the affected ranges. Affected version ranges have not been ingested yet. Check the linked vendor or CERT advisories for patch status. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.
Security analyst
Signals on file: CVSS 7.5, EPSS 0.2%. It is not currently listed in the CISA Known Exploited catalog. Weakness classes: CWE-671. Sources contributing to this record: csaf, cve_org, epss, nvd. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.
Exploitation and remediation
Exploitation evidence
Not listed as known exploited in CISA KEV. Not in CISA KEV or VulnCheck KEV.
Patch and remediation
No required-action text is stored yet. Use the vendor or CERT links in Sources for patch availability.
Safe detection guidance
Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Sep 8, 2026 · NIST NVD
Detected
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
Oct 15, 2026 · NIST NVD
Updated
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
Sources
- CSAF AdvisoriesVendor advisoryNN-2026:20-01:CVE-2026-33389
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.
security.nozominetworks.com - CVE.orgVulnerability recordCVE-2026-33389
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-33389
30-day exploitation probability 0.2%
first.org - NIST NVDVulnerability recordCVE-2026-33389
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 attac
nvd.nist.gov