CVE-2023-33372: Connectedio Connected Io

Critical severity, CVSS 9.8. EPSS: 0.8% chance of exploitation in the next 30 days.

Connected IO v2.1.0 and prior uses a hard-coded username/password pair embedded in their device's firmware used for device communication using MQTT. An attacker who gained access to these credentials is able to connect to the MQTT broker and send messages on behalf of devices, impersonating them. in order to sign and verify JWT session tokens, allowing attackers to sign arbitrary session tokens and bypass authentication.

Affected products

• Connectedio Connected Io: up to and including 2.1.0

Published 2023-08-04. Last modified 2026-06-17.