Hundreds of thousands of tracking devices manufactured by Shenzhen i365 Tech have serious security vulnerabilities, including hundreds across Australia and New Zealand.

The T8 Mini GPS tracker and 30 other models by the same manufacturer are designed to keep children, seniors, pets and possessions safe – ironically, the devices themselves aren't very safe at all.

The devices don't have any encryption, which means they leak real-time GPS coordinates. What's more, attackers could hijack the devices to intercept microphones, phone numbers (through SMS), and take over the device's firmware.

According to Avast researchers, there are approximately 600,000 at-risk trackers in use across the world.

There are also at least 50 mobile apps that use the same unencrypted platform.

What's more, the manufacturer doesn't seem to be doing anything about it. In Avast's words, repeated notifications to the device maker revealing the flaws received no response.

“We have done our due diligence in disclosing these vulnerabilities to the manufacturer, but since we have not heard back after the standard window of time, we are now issuing this Public Service Announcement to consumers and strongly advise you to discontinue use of these devices,” says Avast senior researcher Martin Hron.

He says that buyers should purchase devices that have built-in security features, particularly secure login and data encryption.

Users should also change the default admin passwords to something stronger – but in the case of the T8 Mini trackers, that isn't going to help.

“Using a simple command lookup tool, researchers discovered that all of the requests originating from the tracker's web application are transmitted in unencrypted plain-text. Even more concerning, the device can issue commands beyond the intended uses of GPS tracking, such as:

• Call a phone number, enabling a third-party to eavesdrop through the tracker's microphone
• Send an SMS message, which could allow an attacker to identify the phone number of the device and thus use inbound SMS as an attack vector
• Use SMS to reroute communication from the device to an alternate server in order to gain full control of the device or spoof information sent to the cloud
• Share a URL to the tracker, allowing a remote attacker to place new firmware on the device without even touching it, which could completely replace the functionality or implant a backdoor.”

Avast warns that people should be cautious when setting up cheap or knockoff smartphone devices into their homes – instead, shop with brands that are trusted and will keep data safe.