CVE-2021-21959: Sealevel Seaconnect 370w Firmware

High severity, CVSS 8.1. EPSS: 0.8% chance of exploitation in the next 30 days.

A misconfiguration exists in the MQTTS functionality of Sealevel Systems, Inc. SeaConnect 370W v1.3.34. This misconfiguration significantly simplifies a man-in-the-middle attack, which directly leads to control of device functionality.

Affected products

• Sealevel Seaconnect 370w Firmware: version 1.3.34 only

Published 2022-02-04. Last modified 2026-06-17.