That was my immediate thought, if they have access to your phone at that level recording (voice, packets, gps co-ords) to a file then sending it once it has signal would be trivial. It would provide a misguided level of confidence in their security which could lead to exactly the consequences trying to be avoided.

Got a secret meeting? Don't take your bloody phone.

Of course not taking your phone is a visible data footprint if you're detected in other ways. Secrecy is a pretty hard problem now.

The objective, in this case, is to prevent recording of the proceedings, not keep the very existence of the meeting a secret.

It has been confirmed that some mobile basebands are, in fact, remotely controllable even when a device is apparently off. It isn't a far-fetched scenario.

http://www.seattletimes.com/nation-world/even-if-theyre-off-...

In this case it was a Motorola device on an iDEN network, probably using a Freescale baseband. But it is likely that most major vendors were persuaded to include similar capabilities and that network providers cooperate in providing special signaling to control these capabilities.

Not useless. Just less useful.

It pushes the capacity for your adversary to operate into (slightly) slimmer confines, which is a marginal improvement.

Otherwise, your adversary can behave in an unrestrained manner. No?

One might also argue that giving a violent prisoner left-handed scissors will slow them down and is therefore a marginal improvement.

I can't argue with that: if I had to choose between the two, I'd rather be stabbed by the non-dominant hand. Obviously not being stabbed at all is a much better choice (when available).

I guess. For the kinds of clients who would want this device, this would just be like making it so that you're only a little bit pregnant. You either prevent the eavesdropping or you don't. The only safe tactic is not bring the device anywhere you don't want to be tracked or recorded. Or to technologically prevent it from operating somehow in a way that doesn't rely on verification -- such as taking the battery out, if you can, or putting it in a verified faraday cage that you keep in a soundproof box if you can't. And if you're the kind of person with a life so interesting they need to worry about about phone implants, maybe take battery removability into consideration when you buy the device.

Baseband processors in all mobiles have direct access to the microphone and it is fairly trivial to access remotely. Comes as standard on all stingray devices available to any and all perverts willing to use it.

Only Samsung devices have been shown to give the baseband processor backdoor access to device storage. Afaik.

This also detects when the GPS is used. If the phone has GPS and cell radio (for reception and transmission) disabled, it's a lot harder for any malware to figure out its location (not impossible -- there is some research about identifying locations in a metro network using an accelerometer alone).

While it's easy to prevent the phone from recording your conversation (just place it somewhere out of earshot, maybe next to a noise source for the duration of the conversation alone), it's much harder to prevent it from learning where you're going (if you're taking it with you).

That a security measure is not impossible to defeat does not mean it's useless.

They would have to know the exact meeting time and would use space on the device, which could be noticed.

This case is not a silver bullet, but it's a useful tool.

Or they could record to file only when the radio is off, and transmit directly without recording when it is on.