In case you still thought otherwise, it's not just international men of mystery and Jersey mobsters who need to be mindful of what they say via cellphones these days, it's regular private citizens like you and I.
New documents unveiled by the American Civil Liberties Union (ACLU) pile it high on top of last week's "Great SIM Heist," that grand disinfofest,1 by revealing that Floridian police forces have been using cell phone tower mimicking "Stingray" devices to track the location of specific cell phone users for over a decade. These particular devices, manufactured by the Florida-based Harris Corporation,2 apparently cost taxpayers more than $3 mn since 2008. And that's just the devices, to say nothing of the overhead for their doughnut-munching operators.
This news in notable for its flouting of the rule of law as much as its scale and scope. Authorisation for the use of these devices is apparently no more than "relevance," that is, neither warrants nor probable cause are required, thereby breaching the US Constitution's Fourth Amendment. This has led to a significant number of vaguely described "wanted persons" being tracked, in addition to petty criminals and even your run-of-the-mill public protestor.
It would be surprising if Florida were the only US state treating its citizens like zeks, and ACLU has put this concern to rest with the finding that the Florida Department of Law Enforcement (FDLE) has been generous enough to share its Stingrays with neighbouring Georgia on more than one occasion.
As if this weren't enough, ACLU has found that the FDLE has gone out of its way to hide the use of its technology from judges and courts by concealing information from filings. This information, due to its politically sensitive nature, must be hidden through parallel construction, that is, the use of a superficially plausible historical account of how evidence was acquired by law enforcement that's in fact distinct from the means and methods actually used.3 The value of the Stingray is such that, in one particular case at least, prosecutors even offered the defendant a no-jail plea deal just to keep things mum for one more day.
But this is the Internet, and nothing stays quiet forever. Especially not delusions.
Those interested in tech and privacy (yet outside La Serenissima) were all "Oh noes, SIM cards aren't secure! Which elected representative shall I call first?" when in fact GSM networks have used 'toy crypto' – that is, cryptography readily hacked by sub-state-level actors, as opposed to 'full fat crypto,' as employed by PGP and Bitcoin – from day one, and very much by design. And GTFO if you think that TextSecure, Silent Text, Signal, RedPhone, Silent Phone, or Black Phone are anything other than delusions of digital security, if not outright honey-pots. ↩
Founded in Ohio in 1895, today the Harris Corporation is headquartered in Melbourne, Florida, has annual revenues of $5 bn, employs 13,000 people, and even has a hand in the scandalous F-35 program. ↩
Y'know, like we saw the US Drug Enforcement Agency do with MuckRock and the FBI do with Ross Ulbricht. ↩
So, when you write 'relayed in plaintext' you mean 'unencrypted' or 'in the clear', right? I assume that both voice comms and text are sent via 'toy crypto'. Are you making the case that the 'toy cypto' = 'in the clear' (de facto unencrypted), or that it is literally being sent in the clear?
Butch, a good question. I've seen evidence that the 'toy crypto' is a matter of $30 and the right inclination. So that's the absolute upper bound for security provided by the GSM network. If that weren't a low enough barrier to entry, the #bitcoin-assets expert on the matter suggests that "call is carried as plaintext on the telco wire".
I've been unable to confirm that the call is, as you said, literally being sent in the clear, but the distance between what I can confirm and what I can reasonably conjecture on is exceedingly small.
'Instant Ciphertext-Only Cryptanalysis of GSM Encrypted Communication' (Barkan et al) for one. and so forth.