CVE-2016-9366 Auth bypass in Moxa NPort

Critical 9.8 Published 13 Feb 2017 Updated 2 Jun 2026

Attackers can bypass authentication on Moxa NPort devices by brute-forcing parameters, allowing unauthorized access to the device.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2016-9366?

CVE-2016-9366 is a critical authentication bypass vulnerability in Moxa NPort, published on 13 Feb 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

An issue was discovered in Moxa NPort 5110 versions prior to 2.6, NPort 5130/5150 Series versions prior to 3.6, NPort 5200 Series versions prior to 2.8, NPort 5400 Series versions prior to 3.11, NPort 5600 Series versions prior to 3.7, NPort 5100A Series & NPort P5150A versions prior to 1.3, NPort 5200A Series versions prior to 1.3, NPort 5150AI-M12 Series versions prior to 1.2, NPort 5250AI-M12 Series versions prior to 1.2, NPort 5450AI-M12 Series versions prior to 1.2, NPort 5600-8-DT Series versions prior to 2.4, NPort 5600-8-DTL Series versions prior to 2.4, NPort 6x50 Series versions prior to 1.13.11, NPort IA5450A versions prior to v1.4. An attacker can freely use brute force to determine parameters needed to bypass authentication.

Weakness: CWE-264, CWE-307

Which versions are affected by CVE-2016-9366?

It affects 10 products.

Products include Moxa Nport 5100 Series Firmware, Moxa Nport 5100a Series Firmware, Moxa Nport 5200 Series Firmware, Moxa Nport 5200a Series Firmware, Moxa Nport 5400 Series Firmware, Moxa Nport 5600-8-Dtl Series Firmware and 4 more.

How do I fix CVE-2016-9366?

No fix has been published for CVE-2016-9366 yet. Limit exposure of the affected software until one is available.

Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.

Is CVE-2016-9366 being exploited?

There is no known exploitation of CVE-2016-9366 in the wild and no public exploit code.

Sources

Also known as GHSA-r4qc-5j5j-254j.