[liberationtech] Bizarre behavior of a non-smart mobile phone

[mok-kong shen]

That a modern smartphone with Internet access and a multitude of nice 
features is liable of being hacked similar to a PC is evident. On the 
other hand,  a non-smart mobile phone, of design of the earlier 
generation, unintelligent, clumsy, no Internet access, though yet 
purchasable for telephone and SMS purposes only, could IMHO easily 
mislead one to think that the device may be sufficiently secure against 
malicious manipulations. The fact is however that, if an adversary is 
capable enough to enter the cellular network, he could access the SIM 
card to perform his malicious work. A recent personal experience of mine 
is the following: I bought such a device and a pre-paid SIM card, 
entered the telephone numbers of my friends into its contact address 
list and informed my friends of my new mobile phone number. Soon, though 
at a rather low frequency averaging roughly one event per day, a number 
of my friends complained that I had called them but strangely never 
attempted to say even a single word. It turned out that the device each 
time arbitrarily selected an entry in the contact address list and 
called automatically, which could also be verified by its list of all 
outgoing calls.  As remedy I deleted all telephone numbers of my friends 
in it, leaving however for experimental purpose my own home telephone 
number. One following night I had then the uncommon experience of being 
awoken by a call from my own mobile phone!

M. K. Shen