Android users have been warned after experts discovered that millions of phones had malware loaded on them straight out of the box.

Android is one of the most popular pieces of software in the world, with it used by more than two billion people each month.

However Android users are no strangers to security alerts, with some recent widespread threats being circulated via apps found on the Google Play Store.

Six Android apps that were downloaded a staggering 90million times from the Google Play Store were found to have been loaded with the PreAMo malware.

While another recent threat saw 50 malware-filled apps on the Google Play Store infect over 30million Android devices.

And now Android users are being warned once again about a malware threat, this time after malicious software was discovered on millions of devices running the Google mobile OS.

Maddie Stone, a security researcher on Google’s Project Zero, revealed pre-installed malware was discovered on 7.4million Android devices.

This malware had the ability to take over Android devices and download apps in the background as well as commit ad fraud.

Stone revealed that this pre-installed malware has been found on budget devices that use third-party software.

Stone said the attackers offered genuine services but hid malware in the apps they provided.

Stone revealed the news during the Black Hat cybersecurity conference in Las Vegas, Cnet reported in a post online.

Stone said: “If malware or security issues can make its way as a preinstalled app, then the damage it can do is greater, and that’s why we need so much reviewing, auditing and analysis.”

Stone detailed a number of case studies on pre-installed apps which were threats to Android devices.

These apps affected millions of devices and were able to turn off Google Play Protect to spy on Android users.

Stone said: “If you are able to infiltrate the supply chain out of the box, then you already have as many infected users as how many devices they sell.

“That’s why it’s a scarier prospect and I really hope more researchers join us in vetting these processes.”

As always, Android users can minimise the malware risk they face by having antivirus software installed on their devices.

Keeping up to date with Android updates can also help limit the impact malicious software can have.

• Stay tuned to Express.co.uk for more Android news and updates