CVE-2023-23306: Garmin Connect-Iq

Critical severity, CVSS 9.8. EPSS: 1.2% chance of exploitation in the next 30 days.

The `Toybox.Ant.BurstPayload.add` API method in CIQ API version 2.2.0 through 4.1.7 suffers from a type confusion vulnreability, which can result in an out-of-bounds write operation. A malicious application could create a specially crafted `Toybox.Ant.BurstPayload` object, call its `add` method, override arbitrary memory and hijack the execution of the device's firmware.

Affected products

• Garmin Connect-Iq: from 2.2.0, up to and including 4.1.7

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