[dave at farber.net: [IP] New Short Video: "Is Your Cell Phone Bugged?"]

[coderman]

On 2/15/07, Eugen Leitl <eugen at leitl.org> wrote:
> ...
> In an effort to explain this issue in a more demonstrative
> and somewhat less technical manner, I'm pleased to announce a
> short free video (under six minutes): "Is Your Cell Phone Bugged?"

good stuff.

predominantly the following are the best give away, and seem to apply
to some models and not others:
[via http://lauren.vortex.com/archive/000202.html]

"A well designed bug program could try to minimize the obviousness of
this by quickly dropping the bug call if the phone owner tried to make
an outgoing call, or drop the bug connection if an incoming call tried
to ring through. But if the bug is up and running, that's the only
transmission path that is available on the phone at that time for the
vast majority of currently deployed cell phones."

this is undetectable on some models, and causes a few seconds of "one
way conference" style problems on others.  basically, you answer/call,
and get silence, neither party can hear each other for a few seconds.

-

"But if your battery seems to be running out of juice far too early
(despite what the phone's battery status display might claim), that
might be an indication that your phone is being used to transmit
behind your back (though a worn out battery or inaccurate battery
status display could also be the culprits).

Another clue that a phone may have been transmitting without your
permission is if it seems unexpectedly warm. You've probably noticed
how most cell phones heat up, especially on longer calls. This is
normal, but if you haven't been on any calls for a while and your cell
phone is warm as if long calls were in progress, you have another red
flag indication of something odd perhaps going on."

this is a good indicator, and particularly on some phones with
excellent battery life (some sanyo/motorola models) it becomes real
obvious when unusual battery drain is occurring.

-

"Finally, if you use a GSM phone (like the vast majority of phones
around the world, including Cingular and T-Mobile in the U.S.) you
have a virtually foolproof way to know if you phone is secretly
transmitting in voice mode. You've probably noticed the "buzzing"
interference that these phones tend to make in nearby speakers when
calls or data transmissions are in progress. A certain amount of
periodic routine communications between cell phones and the networks
will occur while the phones are powered on -- even when calls are not
in progress -- so short bursts of buzzing between calls (and when
turning the phones on or off) are normal.

But if you're not on a call, and you hear a continuing rapid
buzz-buzz-buzz in nearby speakers that lasts more than a few seconds
and gets louder as you approach with your phone, well, the odds are
that your phone is busily transmitting, and bugging is a definite
possibility. Note that this particular test is much less reliable with
non-GSM phones that use CDMA (e.g. Sprint/Verizon phones), since
CDMA's technology is less prone to producing easily audible local
interference. This strongly suggests that CDMA phones may be preferred
for such bugging operations."

this is a smoking gun on a GSM phone, and unfortunately it does not
work against CDMA, as mentioned.

take the battery out, it works great. :)