Strange things happen today morning once again. Myself and my wife's mobile phone always connected to Wi-Fi internet while we are in home. Today suddenly observed that automatically mature a call from my wife's phone to my phone without any human intervention.
Is this a Malware or something else because this kind of auto calling has happened second time.
Connection initiated from phone (A) model Nokia Lumia 730 Dual SIM.
This is an odd state of affairs, and it's unusual for any phone to autonomously make calls, unless an application has permissions to do so. The fact that the call is being made from one device to another that you know, makes it even more strange.
Could I ask, is the call established regularly between the devices as the same originator/destination? It could help if you were to whittle your investigation down to the offending originating device firstly.
Also, log in to your router and check the connection tables. Be sure you idenitify every device that is connected. for extra protection, change your wifi passwords, and ensure you regularly check your router logs and ensure that the incidents of logging in are all accouted for.
Use a trial version of anti-virus to see if anything is detected there for starts. Your listing two different OSes which makes malware a bit of a long shot as mobile malware is generally very targeted.
Second thing to check is what Wi-Fi are these phones connecting? If you live in the city where I have seen over 200 available connections would mean you have your work cut out for you to identify a specific connection if its just a hijacking. This really isn't as hard as you might think.
Third, consider both phones to be breached and untrusted. Change the passwords and if need be have both phones wiped and reloaded with a fresh OS image.
It is possible to do a full phone forensic examination but that will put you without a phone for a couple of days and would be prohibitively expensive unless you can DIY.
Let us know what you find or decide so we can satisfy the technical curiosity, if you would please.