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Comment by NoiseBert69 | Hacker News Reader

Why aren't they using the official lawful interception interfaces?

They will get all the data. Not only voice, data and SMS/RCS.

All modern smartphones (like Pixels) allow you to switch off 2G. They even warn if you want to activate it.

Lawful interception requires things like paperwork, warrants, probably cause, and some kind of reason why you need to tap cellular comms in the first place. If you're operating a deportation agency in the style of roaming gangs of officers, you're probably not going to want to wait for the courts to dismiss your brute-force attempts to find illegals behind every door you break down.

The anti-2G security measure is pretty much exclusive to a few high-end phones as far as I can tell. iPhones can enable it with lockdown mode (which also disables things like JIT and can make websites and app run slower), Google has added a toggle, and I think a few other manufacturers have it too, but you need support in the modem firmware to actually do anything with it.

Even then, 3G and 4G can also leak identifiers if you can fake being a base station. The identifiers are not as easy to obtain as on 2G, but there's a reason 5G added a masking feature to LTE. Especially combined with access to an SS7 capable line, you can pretty much replicate all of the 2G hacks with cellular tech at least up to 4G, maybe even newer than that.

Cellular firmware protection mechanisms seem to be targeting 2G exploitation so far. It'd be extremely unpractical (and probably impossible) to enforce some kind of "5G NR only" mode, but without such a mode you're going to be at risk of Stingray-like devices.

> Lawful interception requires things like paperwork, warrants, probably cause, and some kind of reason why you need to tap cellular comms in the first place.

In case folks hadn't been paying attention, probable cause isn't even worth their trouble when arresting someone these days.

> “DHS law enforcement uses ‘reasonable suspicion’ to make arrests,” DHS Assistant Secretary Tricia McLaughlin said in a statement to The Associated Press

https://www.newsweek.com/trump-admin-race-baiting-lawsuit-wo...

> The anti-2G security measure is pretty much exclusive to a few high-end phones as far as I can tell.

I've got it on my phone which I think is mid-market at best: moto g stylus 5g - 2023. Snapdragon 6 Gen 1. ~ $250 in 2023.

That's great to hear. Last time I looked around in the cheaper segment, very few phones seemed to come with the feature.

It's part of newer versions of stock android.

Lawful interception requires things like paperwork, warrants, probably cause

Technically yes but there are back-room agreements to bypass this. I used to have warrants on my desk to set up call tracing in the 90's and eventually I was told to not require them any more and just leave test system and modems enabled logging disabled so agents could set up their own call tracing. The people I worked for had no skin in the game as they were all from the EU. I would be very surprised if this was no longer a thing. If anything I would expect it to be much simpler and more stream-lined by now, probably some HTTPS API end-point and some app on their phone.

In fairness to the agents some things are time sensitive like kidnappings / abductions. Provided logging is not disabled I think it is fine they have real time access if someone actually audits the logs and matches them up to incidents much like license plate queries by cops are supposed to be audited.

> Why aren't they using the official lawful interception interfaces?

Probably for the same reason they're wearing masks

> Why aren't they using the official lawful interception interfaces?

They may not want to leave a paper trail.

“To obtain a [legal] wiretap order, law enforcement must demonstrate probable cause to a judge” [1]. Given ICE has been arresting Americans, they probably aren’t bothering with cause. Legal intercepts also require “minimization procedures to limit the interception of conversations unrelated to the investigation,” which ICE may not want to do. And perhaps most importantly, “violations of 18 U.S.C. § 2511 are considered federal felonies,” with those convicted facing criminal penalties and being subject to civil liability.

I hate to make this analogy, but it’s akin to the Gestapo’s NBH obsession. They knew they were acting illegally, and didn’t want to leave the evidence that would convict them.

[1] https://legalclarity.org/what-is-wiretapping-and-when-is-it-...

But, isn't intercepting communications using a fake cell tower a wiretap?

Of course it is. But good luck proving how they got the information.

Assuming there is even a venue where evidence would be provided for the purpose of being looked at

>But, isn't intercepting communications using a fake cell tower a wiretap?

The article doesn't actually mention what ICE is actually using the cell site simulators for. It's possible that they're only collecting IMSIs and not text/voice traffic, which might still be wiretapping, but it'd be more difficult to argue in front of a judge.

Are you familiar with the concept of parallel construction?

If evidence of the wiretap never needs to be entered into the official record, did it really exist in the first place?

I wonder if there's an argument that mobile phones are using publicly-owned broadcast spectrum, and therefore, like when walking around in public, there isn't an expectation of privacy. Ham radio rules for example prohibit encryption because they are using public airwaves.

It used to be possible to just set up an analog receiver and you could listen to nearby cell phone calls.

I actually find that a decent argument, but I believe it’s already been shut down. When police used thermal imaging to “observe” a house, without doing anything they thought required a warrant, the Supreme Court decided it was too intrusive ( https://supreme.justia.com/cases/federal/us/533/27/#tab-opin... ). But if I understand the ruling correctly, if the police make it well-known that they have the ability to do something intrusive, then they don’t need a warrant.

Intercepting cell phone communications is restricted by law. This was enacted when public officials had their clear AMPS phone calls recorded with legally owned passive radios.

We're far beyond the point of them caring about the laws. Judges are granting temporary residency to immigrants in court proceedings, and then those same people are detained and deported by ICE as soon as they walk out of the courtroom.

> They may not want to leave a paper trail.

This makes sense, considering the regime is hiring Jan 6th insurrectionists like Jared Wise. Legality has gone out the window.

Another possibility not mentioned here is simply demonstrating that they can get away with not doing so.

Who says they aren't?

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