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If you fear your phone has been cloned, your first step should be to reach out to your carrier to ask if anyone has attempted accessing your phone account. Most cloning attacks target your SIM card so watch out for periods when you're unable to make or receive calls and text messages, and be careful about suspicious messages that ask you to restart your phone. Likewise, watch out for unusual calls and charges on your phone bill. While much less likely, a malware-infected phone will perform poorly, lose battery quickly, and get surprisingly warm even if you aren't doing any processor-intensive tasks.
What is phone cloning? SIM Swap attacks explainedHow to tell if your phone has been clonedWhat to do after your phone gets cloned
What is phone cloning? SIM Swap attacks explained
Phone cloning isn’t as simple as some spy movies might make it seem, but it is a genuine concern for any smartphone user. There are two ways a malicious actor can clone your phone. The first is to copy your phone’s SIM card data and IMEI (International Mobile Equipment Identity) information to duplicate your smartphone’s cellular line on another device. They can make calls and send messages for phishing scams, access one-time banking, and other account passwords, or make expensive calls to premium-rate numbers.
Another type of phone cloning is where someone can copy or access your phone’s data. A few legal spy apps are available for parents to monitor their child’s phone activity. But for the most part, a hacker could install malicious apps on your phone through malware. However, the vast majority of attacks require physical access to the device. So it’s important to never let your phone end up in the hands of someone you don’t trust. We’d recommend setting up a secure password or PIN so only you can get past the lockscreen.
Always set a secure PIN or password to prevent someone from accessing your phone.
You may fall victim even if an attacker never gets physical access to your smartphone. In what’s known as a SIM swap attack, a malicious person could impersonate your identity and ask your carrier to reissue a new SIM card. They can then use this SIM card to send and receive text messages, which may unlock access to online services like banking and email.
Likewise, there’s a lot hackers can do after malware is installed on your phone. Keyloggers let them see everything you type on your phone, like account login information. They might also be able to access private documents, photos, and videos and leak them, try and scam friends, family, and other contacts, or install ransomware on your devices.
How to tell if your phone has been cloned
1. Check your phone for malware
Ryan Haines / Android Authority
There are several ways you can tell if your phone has malware. The most obvious issue to watch out for is performance problems. Your phone might suddenly become sluggish or crash and freeze often. You might also notice rapid battery drain and overheating issues. Of course, software bugs and other glitches might cause these issues. You should check out our guides to speed up your smartphone and fix Android battery drain issues.
In the case of malware, look for behavior beyond what a software bug might cause. To a point where your phone is almost unusable. A noticeable increase in pop-up ads, strange emails, and weird text messages are also signs of a malware-ridden phone.
You can check your device for malware and go through the phone’s app list (go to Settings > Apps) and look for apps you don’t recognize.
