(((Smartphones with bug apps can of course log audio to flash, if lots of it is present -- when it is sending, a LED toy indicating HF transmission could come handy))) http://lauren.vortex.com/archive/000202.html December 03, 2006 How To Tell If Your Cell Phone Is Bugged Greetings. A story is making the rounds right now regarding FBI use of cell phones as remote bugs. I originally wrote about this concept in my PRIVACY Forum in 1999 ("Cell Phones Become Instant Bugs!") so the issue is real, but we still need to bring the current saga back down to earth. This discussion doesn't only relate to "legal" bugs but also to the use of such techniques by illegal clandestine operations, and applies to physically unmodified cell phones (not phones that might have had separate, specialized bugs physically installed within them by third parties). There is no magic in cell phones. From a transmitting standpoint, they are either on or off. It is true that many phones have an alarm feature that permits them to "wake up" from their usual "off" state. However, this is not a universal functionality, even in advanced phones such as PDA cell phones, which now often have a "totally off" mode available as well. It is also true that some phones can be remotely programmed by the carrier to mask or otherwise change their display and other behaviors in ways that could be used to fool the unwary user. However, this level of remote programmability is another feature that is not universal, though most modern cell phones can be easily programmed with the correct tools if you have physical access to the phones, even briefly. But remember -- no magic! When cell phones are transmitting -- even as bugs -- certain things are going to happen every time that the alert phone user can often notice. First, when the phone is operating as a bug, regular calls can't be taking place in almost all cases. 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 phones. Some very new "3G" phones technically have the capability of running a completely separate data channel -- in which voice over IP data could be simultaneously transmitted at full speed along with the primary call (conventional GSM data channels -- GPRS/EDGE -- typically block calls while actively transmitting or receiving user data). But this is pretty bleeding-edge stuff for now, and not an issue for the vast majority of current phones. Of course, if a cell phone is being used as a remote bug, the odds are that the routine conversations through that phone are also being monitored, right? So this "one call at a time" aspect isn't as much of a limitation to bugging as might otherwise be expected. Want to make sure that your phone is really off? Taking out the battery is a really good bet. Don't worry about the stories of hidden batteries that supposedly can be activated remotely or with special codes. The concept makes no sense in general, and there just isn't room in modern cell phones for additional batteries that could supply more than a tiny bit of added power, if any. But if your battery seems to be running out of juice far too early (despite what the battery status display might claim), that might be an indication that your phone is being used to transmit behind your back (or it might be a worn out battery and a typically inaccurate battery status display). 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. 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 another virtually fullproof way to know if you phone is secretly transmitting. 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. A variant form of CDMA (called "WCDMA") is used for the high speed data channel (but not the voice channel) on new 3G GSM phones. Since voice could theoretically be encoded onto that channel as I mentioned above -- which would be harder to detect than the main GSM voice channel -- this is a technology that will bear watching. The odds of most people being targeted for bugging are quite small. But it's always better to know the technical realities. Don't be paranoid, but be careful. --Lauren-- -- Eugen* Leitl <a href="http://leitl.org">leitl</a> http://leitl.org ______________________________________________________________ ICBM: 48.07100, 11.36820 http://www.ativel.com 8B29F6BE: 099D 78BA 2FD3 B014 B08A 7779 75B0 2443 8B29 F6BE [demime 1.01d removed an attachment of type application/pgp-signature which had a name of signature.asc]