Garmin Forerunner 235 before 8.20 is affected by: Array index error. The component is: ConnectIQ TVM. The attack vector is: To exploit the vulnerability, the attacker must upload a malicious ConnectIQ application to the ConnectIQ store. The ConnectIQ program interpreter trusts the offset provided for the stack value duplication instruction, DUP. The offset is unchecked and memory prior to the start of the execution stack can be read and treated as a TVM object. A successful exploit could use the vulnerability to leak runtime information such as the heap handle or pointer for a number of TVM context variables. Some reachable values may be controlled enough to forge a TVM object on the stack, leading to possible remote code execution.

Garmin Forerunner 235 before 8.20 is affected by: Integer Overflow. The component is: ConnectIQ TVM. The attack vector is: To exploit the vulnerability, the attacker must upload a malicious ConnectIQ application to the ConnectIQ store. The ConnectIQ program interpreter fails to check for overflow when allocating the array for the NEWA instruction. This a constrained read/write primitive across the entire MAX32630 address space. A successful exploit would allow a ConnectIQ app store application to escape and perform activities outside the restricted application execution environment.

Garmin Forerunner 235 before 8.20 is affected by: Array index error. The component is: ConnectIQ TVM. The attack vector is: To exploit the vulnerability, the attacker must upload a malicious ConnectIQ application to the ConnectIQ store. The ConnectIQ program interpreter fails to check the index provided when accessing the local variable in the LGETV and LPUTV instructions. This provides the ability to both read and write memory outside the bounds of the TVM context allocation. It can be leveraged to construct a use-after-free scenario, leading to a constrained read/write primitive across the entire MAX32630 address space. A successful exploit would allow a ConnectIQ app store application to escape and perform activities outside the restricted application execution environment.

Garmin Forerunner 235 before 8.20 is affected by: Buffer Overflow. The component is: ConnectIQ TVM. The attack vector is: To exploit the vulnerability, the attacker must upload a malicious ConnectIQ application to the ConnectIQ store. The ConnectIQ program interpreter trusts the string length provided in the data section of the PRG file. It allocates memory for the string immediately, and then copies the string into the TVM object by using a function similar to strcpy. This copy can exceed the length of the allocated string data and overwrite heap data. A successful exploit would allow a ConnectIQ app store application to escape and perform activities outside the restricted application execution environment.

In Garmin Connect 4.61, terminating a LiveTrack session wouldn't prevent the LiveTrack API from continued exposure of private personal information. NOTE: this is disputed by the vendor because the LiveTrack API service is not a customer-controlled product.

The `Toybox.Graphics.BufferedBitmap.initialize` API method in CIQ API version 2.3.0 through 4.1.7 does not validate its parameters, which can result in integer overflows when allocating the underlying bitmap buffer. A malicious application could call the API method with specially crafted parameters and hijack the execution of the device's firmware.

The permission system implemented and enforced by the GarminOS TVM component in CIQ API version 1.0.0 through 4.1.7 can be bypassed entirely. A malicious application with specially crafted code and data sections could access restricted CIQ modules, call their functions and disclose sensitive data such as user profile information and GPS coordinates, among others.

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.

The `news` MonkeyC operation code in CIQ API version 1.0.0 through 4.1.7 fails to check that string resources are not extending past the end of the expected sections. A malicious CIQ application could craft a string that starts near the end of a section, and whose length extends past its end. Upon loading the string, the GarminOS TVM component may read out-of-bounds memory.

The `Toybox.GenericChannel.setDeviceConfig` API method in CIQ API version 1.2.0 through 4.1.7 does not validate its parameter, which can result in buffer overflows when copying various attributes. A malicious application could call the API method with specially crafted object and hijack the execution of the device's firmware.

The `Toybox.Ant.GenericChannel.enableEncryption` API method in CIQ API version 3.2.0 through 4.1.7 does not validate its parameter, which can result in buffer overflows when copying various attributes. A malicious application could call the API method with specially crafted object and hijack the execution of the device's firmware.

The GarminOS TVM component in CIQ API version 2.1.0 through 4.1.7 allows applications with a specially crafted head section to use the `Toybox.SensorHistory` module without permission. A malicious application could call any functions from the `Toybox.SensorHistory` module without the user's consent and disclose potentially private or sensitive information.

The GarminOS TVM component in CIQ API version 1.0.0 through 4.1.7 is vulnerable to various buffer overflows when loading binary resources. A malicious application embedding specially crafted resources could hijack the execution of the device's firmware.

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.