CVE-2026-33389 Security feature bypass in Arc
Attackers can intercept credentials via man-in-the-middle attacks due to disabled certificate validation in Smart Polling, allowing device access and tampering.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-33389?
CVE-2026-33389 is a medium-severity vulnerability in Nozomi Networks Arc, published on 8 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
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.
Weakness: CWE-671
Which versions are affected by CVE-2026-33389?
How do I fix CVE-2026-33389?
No fix has been published for CVE-2026-33389 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-33389 being exploited?
There is no known exploitation of CVE-2026-33389 in the wild and no public exploit code.
Sources
Also known as GHSA-8g88-35qx-36v7.