CVE-2023-23300: Garmin Connect-Iq

Critical severity, CVSS 9.8. EPSS: 1.3% chance of exploitation in the next 30 days.

The `Toybox.Cryptography.Cipher.initialize` API method in CIQ API version 3.0.0 through 4.1.7 does not validate its parameters, which can result in buffer overflows when copying data. A malicious application could call the API method with specially crafted parameters and hijack the execution of the device's firmware.

Affected products

• Garmin Connect-Iq: from 3.0.0, up to and including 4.1.7

Published 2023-05-23. Last modified 2026-06-17.