Cloned SIM

[SubjectSigma]

So I gave my old phone to a friend, and he said that the phone randomly sends messages to people on his contacts list (pretty vulger messages at that) and I'm having trouble wrapping my head around it.  How would someone do that.  

Explanation 1

Someone Cloned the SIM

Very unlikely considering that the only people to have the phone for more than an hour

Explanation 2

AT&T somehow managed to activate a SIM with the same IMSI and KI which is   HIGHLY unlikely

[Ivyk]

Same way your email can get infected and send random spam mails to all your contacts.

Not sure it would work on a phone though.

[SubjectSigma]

Same way your email can get infected and send random spam mails to all your contacts.

Not sure it would work on a phone though.

So basically a MMS that can read a phone identity, lol