WhatsApp fans need to be aware of a malware threat that affects millions of Android devices.

WhatsApp is the world’s most popular chat app and Android is one of the most used pieces of software in the globe.

WhatsApp is used by 1.5billion people every month while Android runs on over two billion devices monthly.

And the huge WhatsApp and Android userbase have now been targeted by a major security threat which hits a weakness in the Google mobile OS.

Security experts are warning that as many as 25million Android fans have been affected by the malware dubbed Agent Smith.

Named after the nefarious villain from The Matrix films, the malware replaces apps such as WhatsApp with fake ones that generate ad revenue for scammers.

Users in the UK are among those affected, alongside Android users in the US and Australia.

WhatsApp fans were alerted about the Android security threat by experts at Check Point, who outlined the Agent Smith malware in a blog post.

They said: “In the Wachowskis’ classic Matrix trilogy, ‘Agent Smith’ famously describes the human race as a species that multiplies until every resource is consumed.

“In reality, it is the ‘Agent Smith’ of the mobile malware world that is the real virus – and is spreading at alarming rates.

“Check Point Researchers recently discovered a new variant of mobile malware that has quietly infected around 25 million devices, while the user remains completely unaware.

“Disguised as a Google related application, the core part of the malware exploits various known Android vulnerabilities and automatically replaces installed apps on the device with malicious versions without the user’s interaction.”

Check Point added: “‘Agent Smith’ is being used to for financial gain through the use of malicious advertisements.

“However, it could easily be used for far more intrusive and harmful purposes such as banking credential theft and eavesdropping.

“Indeed, due to its ability to hide its icon from the launcher and impersonate existing user-trusted popular apps, there are endless possibilities for this sort of malware to harm a user’s device.”

While users in the UK, US and Australia have been impacted it has mainly affected those in India and Asian countries like Pakistan and Bangladesh.

Unlike other high-profile malware threats, Agent Smith has not been spread via the official Google Play Store.

Instead it has been spread via 9apps.com, a third-party app store owned by China’s Alibaba.

If you have been affected by the Agent Smith Android threat then here’s how you can remove any nefarious apps on Android, according to Check Point…

– Go to Settings Menu

– Click on Apps or Application Manager

– Scroll to the suspected app and uninstall it

– If it can’t be found then remove all recently installed apps

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