Vulnerability · Published Sep 8, 2026 · Assigned by Nozomi
CVE-2026-33389Disabled and non-configurable certificate/host key validation in Smart Polling in Guardian/CMC before 26.3.0 and Arc before v2.7.0
High 7.5
In plain English
A high-severity security flaw in Arc from Nozomi Networks. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 6% of all known vulnerabilities).
Official 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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Nozomi Networks | Guardian | 0 – before 26.3.0 |
| Nozomi Networks | CMC | 0 – before 26.3.0 |
| Nozomi Networks | Arc | 0 – before 2.7.0 |
Weakness: CWE-671 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:L