Modern-day spying: sometimes old technology is more secure

https://www.economist.com/technology-quarterly/2024/07/01/sometimes-the-old-ways-of-espionage-are-the-best

by hilux • 2 years ago

177 138 2 years ago

economist.com

tahoeskibum• 2 years ago

Sounds like the storyline for Battlestar Galactica :-)

trod1235• 2 years ago

The technical director on that remake had a sound head on his or her shoulders.

They correctly treated many aspects and details that today go ignored and addressed many of the issues that apply to us today with regards to adversaries who can by nature react faster than we can perceive.

The solution had cost tradeoffs, but in the end it proved the correct decision through virtue of the fact that the story continued (and they weren't all killed off in episode one).

czl• 2 years ago

it proved the correct decision through virtue of the fact that the story continued (and they weren't all killed off in episode one).

In the show’s fictional plot, the decision seems correct because the story continued and the characters survived. However, we shouldn't judge decisions in real life by how they are portrayed in fiction. In modern fiction, decisions are often shaped to please audiences, not to reflect real-world correctness. Thus, it may not be wise to judge these fictional decisions by the same standards we use in real life.

heinrich5991• 2 years ago

https://archive.is/G9g7P

bmurray7jhu• 2 years ago

Matt Blaze's analysis of the flawed OTPs used by Cuban numbers stations: https://www.mattblaze.org/blog/neinnines/

_n_b_• 2 years ago

And his recording of the Cuban numbers station, if you want to hear what these sound like: https://www.mattblaze.org/private/17435khz-200810041700.mp3

Here's a sample of the referenced "Linconshire Poacher": https://priyom.org/media/247818/e3.mp3

ghayes• 2 years ago

Trying to understand why the Nein Nines could happen. My first thought for a “fill” algorithm would be to just fill with zeros, and hence read out the pad, since it is going to be used up anyway. But I suppose that’s bad since if it did accidentally get re-used then that cyphertext would be fully compromised (versus say having two cyphertexts from the same pad to run a frequency analysis against). Another fill would be to add random data and pad against it, but then if your random data is flawed, you may still leak the OTP. So, I guess the actual algorithm must be derived from the OTP, but not padded with it? (Since if it were padded, there is no way to avoid a 9 digit). It just seems like zero or semi-random fill seems safer…

pwg• 2 years ago

My first thought for a “fill” algorithm would be to just fill with zeros, and hence read out the pad, since it is going to be used up anyway.

That also would use up the pad when there are no messages, requiring some secure way to get a new pad to the operatives when their existing pad is consumed. This is difficult enough (secure delivery of new pad) that it is unlikely that spy-HQ wishes to consume pad data for fill.

But I suppose that’s bad since if it did accidentally get re-used then that cyphertext would be fully compromised

Yes, if they reused any part of any pad for more than one single message, they have compromised (and revealed) the contents of the reused pad messages. This is the other difficulty with OTP's. The OTP data must never be reused. Which is alo why spy-HQ would not want to use it (the OTP) up for the fill, because to avoid reuse then they have to get new pad material to the operatives in some secure way.

So, I guess the actual algorithm must be derived from the OTP, but not padded with it?

The 'implication' of the article is that the fill is just random data (without using up any pad material). Possibly with the appropriate headers in place so that it looks indistinguishable from a read message in the same slot.

The further implication is that the Cuban station did something essentially like this:

    for (count=0; count<20; count++) {
        send(int(rand()*9));
    }

With a rand() implementation that returned a number from zero to 1.0 exclusive of 1.0 and an int() implementation that merely truncated any fraction from the multiplication. With the result that 9 is never sent.

nneonneo• 2 years ago

It says in the article me that the spies would decrypt and verify a header before moving on to the main message. Presumably the fill messages would simply not have a valid header, or it would have a special header that indicated it was a fill message.

fallinditch• 2 years ago

For a more thorough description of OTP see https://cryptosmith.com/2007/06/09/one-time-pads/

andix4• 2 years ago

I think those old technologies are still around, because it's hard to train older spies on new technology. They learned that knowledge decades ago and would have a hard time to learn new things. So they let them use the stuff they know, instead of risking some boomer making an opsec mistake by updating their Facebook status on a secure device while doing sensitive communication.

jrexilius4• 2 years ago

I would wager that is has more to do with leveraging existing infrastructure that is commonly deployed to more than just G7 nations and working with people in those countries who may not have a Q branch handy nor could afford to be caught with gear-turned-evidence.

As well, as any honest engineer knows, new tech is rarely reliable and bug free. You may adopt it for other benefits, but assurance is generally not one of them. So if lives depend on something, you may keep using things that have been proven reliable.

CapitalistCartr• 2 years ago

At least the USA and our allies are extremely conservative in adoption of unproven tech and have extremely high standards for security. The article states "modern methods are not safe" and is correct, in my experience. Numbers stations and One-Time Pads are a well-known and proven method, not just the encryption, but the entire process from delivering the pads to receiving the messages.

cqqxo4zV46cp2• 2 years ago

This is such a HN response. “If they aren’t using new technology, it’s gotta be [disparagement and putdowns, without any consideration being paid to whether or not the ‘newer’ stuff is worth it, let alone better]”

andix4• 2 years ago

Around 10 years ago there were some Russian "illegals" captured in Germany. It was really a lot like in the TV show "The Americans".

They seemed to have communicated a lot with radio and coded messages. They also used some Windows software to decode some of those messages. And exactly there they made a mistake and some messages could be restored.

It seems like they only got very limited recurring training after their initial training in the 90s. So they might have had very limited IT opsec knowledge.

The analog radio technology is also far from perfect. In their case the neighbours became suspicious, because they never opened the door at specific times, probably when their transmissions were scheduled. They also sent some radio transmissions from a nearby hill, that might have played a part in their capture.

I'm convinced that some encrypted messages over a commonly used messenger or email provider would be way more secure. They would just disappear within billions of other encrypted messages.

ClumsyPilot3• 2 years ago

hard to train older spies on new technology

It’s even harder to train new people in Old technology. Just write a code base in Fortran And see how hard it is to find a developer.

I’m quite confident you could send messages all day using the methods of Ancient Rome without being ever detected.

lazide• 2 years ago

Hz pm!

andix4• 2 years ago

It’s even harder to train new people in Old technology

My thought is, that new people are trained on modern technology (how to acquire and set up a secure laptop OS or how to configure a smartphone), and older employees still "run" on the old technology.

hilux3• 2 years ago

Did you read the article?

andix4• 2 years ago

Yes, I did.

Lapsa• 2 years ago

localfirst6• 2 years ago

how do you create encrypted communication that isn't easily triangulated?

some youtubers are pushing LoRa but its hardly secure or encrypted

creating your own number station requires shortwave broadcast which takes up a ton of power and your station is known

the only way to break 5E is good old paper with one time pad encryption with dead drops but its hardly efficient

oceanplexian• 2 years ago

This is exactly what Meshtastic is designed to do. Messages are encrypted with AES256, its extremely low power (And thus hard to triangulate), and can use a low powered repeater, hiding the location of a sender using a directional antenna. Nothing is impossible in terms of tracing or finding vulnerabilities but Meshtastic makes it a pain for an adversary.

KaiserPro2• 2 years ago

meshtastic is terrible for avoiding triangulation. you operate in receiver mode and you have a unique ID. so you can send nonsense packets to that ID repeatedly and it'll send them right out again.

Any kind of forwarding system with static IDs is very much not triangulation resistant.

user32489318• 2 years ago

Instinct tells me that you can have one of three, non triangulatable, secure/encrypted or high bandwidth

localfirst6• 2 years ago

lot of us would take first two over high bandwidth

so far im seeing starlink + modded smartphone

"s4tll1te p1r4cy" that ppl outside N America ignore but supposedly risky for everyone else

variations on LoRa (still not convinced it can evade tri)

jrexilius4• 2 years ago

LoRa is just a transport layer. You can do whatever encryption you want and LoRaWAN has some basic encryption built in. It's hard(er) to triangulate if you don't have constant traffic (like route updates in mesh, or heavy concentrated users like at a concert or protest), but be aware that AWS sidewalk (and all the alexa devices fielded in peoples homes, etc.) run LoRa antennas and traffic. So in the US, Amazon could do a reasonable job at triangulation of frequent emitters. In China and EU there is infrastructure in place (5G/SDR stuff overtly) that can do a pretty good job at triangulating a wide band of RF emitters.

Meshtastic is not really designed to avoid that, but more for resiliency and off-grid type scenarios. Your best bet of really avoiding triangulation by state or telco level infratructure is to get creative with frequency and even transport layer hopping. None of which is really consumer friendly.

[edit-to-add] another tactic to for low probability detection is to hide in noise on high traffic channels. basically figure out what their filter sensitivty is and see if you can go below that threshold and still maintain coherent channel, etc.

immibis4• 2 years ago

On the subject of hiding in high traffic channels, I wonder if I can even mention satellite piracy without getting on more watchlists. It's a thing that exists. Many satellites are relatively unsophisticated signal repeaters, and the antenna that receives their uplink signal isn't very directional, either. Or so I heard. Some companies have been known to go crazy trying to find out who's transmitting to their satellite that shouldn't, because they could be almost anywhere. Of course, if caught, they go to prison for a long time.

immibis4• 2 years ago

If you're an average Hacker News user, you use Tor over the Internet. If you're a more paranoid one, you use Tor to access your Protonmail account that you use with Mixmaster.

localfirst6• 2 years ago

Tor is neither anonymous or safe, there has been variety of vulnerabilities, zero days.

The other options involving radios, satellites is far more sexy

KaiserPro2• 2 years ago

isn't easily triangulated?

Depends.

Anything with high enough power is triangulateable, if you have either enough time, or enough listening equipment.

also what precision are we talking about?

on longwave you can bounce radio signals about quite a lot, but you lack bandwith, and the antenna are huge.

If you have a high band width transmitter, and you are doing async transmission, ie send a message when you are far away, then its not as critical.

superkuh• 2 years ago

Near verticial incidence skywave https://en.wikipedia.org/wiki/Near_vertical_incidence_skywav... using the HF bands and HF antenna very close to the ground. This will cause your signal to basically only go up and then bounce off the ionosphere. This causes you signal to skip a ring of a ~100 miles around you forming a donut of gound locations that can receive it from the ionosphere bounce.

The triangulation will not be to your location to to the ionospheric bounce. Locally it'll propagate via groundwave but that will quickly die out with the first hills and valleys.

A network of ~300 mi seperated stations doing NVIS could be fairly hard to locate. To make it slightly harder you could try using ultrawide bandwidth modulations (UWB) at HF freqs but propagations differences between the freqs will make it hard.

I say all of this but it depends on your threat model. Nowadays major nations have electromagnetic signals intelligence satellites even for HF up in orbit and have a line of sight to everything.

guardianbob• 2 years ago

Fax Machines FTW baby

nicbou• 2 years ago

If that were the case, German intelligence would have a far better track record

dfc• 2 years ago

This is the article by Ingesson and Andersson.

Clandestine communications in cyber-denied Environments: Numbers stations and radio in the 21st century

https://www.tandfonline.com/doi/epdf/10.1080/18335330.2023.2...

barbs• 2 years ago

Sort of related - someone uses Windows 98 and tries to install a virus, but can't.

https://youtu.be/mbbRUDexuBk

Loughla• 2 years ago

That is amazing.

Security by obsolescence.

sreejithr• 2 years ago

No shit

jwsteigerwalt• 2 years ago

(1) a one time pad is and will remain highly secure (2) blocking shortwave radio (even if you are a nation state) is more difficult then taking down web assets. (3) there are benefits to security by obscurity when its part of a layered approach with constant maintenance and feedback (#3 is my controversial take)

cqqxo4zV46cp2• 2 years ago

The fact that 3 is controversial is telling of the sad state of the security knowledge of techies generally. The most people seem to be able to do is to cargo cult / parrot, misunderstand, and misappropriate quips like “security by obscurity bad!” when it, all else equal, is a perfectly reasonable and often useful additive measure to take if it’s available to you.

willis936• 2 years ago

You can even poke holes in it using their own terminology. Obscurity is equivalent to minimizing attack surface area. The less adversaries know about your system the smaller of a target it is.

kibwen• 2 years ago

A knee-jerk aversion to anything halfway adjacent to "security by obscurity" is flawed, but this reaction to that aversion is also flawed.

Instead of trying to suggest "security by obscurity is fine, actually, and don't worry about it", it's time for us to just stop being pithy and start being precise: your cryptosystem should be secure even if your adversaries understand everything about it. If that is true, then you can (and, in the real world, almost certainly should) add defense in depth by adding layers of obscurity, but not before.

chmod775• 2 years ago

The most people seem to be able to do is to cargo cult / parrot, misunderstand, and misappropriate quips like “security by obscurity bad!"

That is the point. It is a good rule of thumb for people who don't know much about security. Anything they create trying to add more security to their system is more likely to do the opposite.

If you think you know better, feel free to ignore it. Just be aware you wouldn't be the first who thought they knew what they were doing or even the first who did know, yet still messed up.

ef32d2d• 2 years ago

Yeah. I think it's the result of conflating theoretical cryptography and practical IT security. Kerckhoffs's principle is true in the theoretical domain and it's certainly important that the designers of standardised crypto algorithms adhere to it but it doesn't follow that it's pointless to change your SSH port.

adrian_b• 2 years ago

While “security by obscurity” may be good for some spy agency as an additional layer over a system that would remain secure even if it were published, most people are right to say that “security by obscurity bad!”, based on the known history of such systems.

The reason is that, without any exception, every time when some system that used “security by obscurity” has been reverse engineered, regardless if it was used for police communications, mobile phone communications, supposedly secure CPUs etc. it was discovered that those systems have been designed by incompetent amateurs or perhaps by competent but malevolent professionals, so that those systems could be easily broken by those who knew how they worked.

“Security by obscurity” is fine for secret organizations, but for any commercial devices that incorporate functions that must be secure it is stupid for a buyer to accept any kind of “security by obscurity”, because that is pretty much guaranteed to be a scam, regardless how big and important the seller company is.

Obscurity is OK only when it is added by the owner of the devices, over a system that is well known and which has been analyzed publicly.

Natsu• 2 years ago

This misunderstands how "security by obscurity" came about, because there are good and bad types of obscurity. Back in the 1800s people were selling shoddy locks that were easy to pick and they were mad that people were disclosing lock picking methods: https://www.okta.com/identity-101/security-through-obscurity...

This history repeated later, with people making shoddy cryptography where they didn't want anyone to know how it worked, and similar things, most of which got broken in embarrassing ways. This sort of obscurity was actively harmful and let people sell defective products that people relied upon to their detriment.

Meanwhile, there are good types of obscurity, too. For example, there are the information disclosure CWEs that tell users of products not to disclose version numbers, stack traces, etc. to users, and this sort of "obscurity" is perfectly reasonable and widely accepted.

So it's not the case that all things that might be termed "obscurity" are bad.

localfirst6• 2 years ago

" there are benefits to security by obscurity when its part of a layered approach with constant maintenance and feedback"

im not sure i understand what this means, can you provide an example and why its controversial?

do you mean a one time pad using memes via image steganography on heavy traffic forums? I recall this is what North Korean spies used to do in early 2000s

michaelt2• 2 years ago

im not sure i understand what this means, can you provide an example and why its controversial?

There is a longstanding tradition of vendors of mediocre 'security' systems using trade secrets/restrictive license terms/anti-hacking laws to cover up their mediocrity.

If you're shopping for a garage door opener and one vendor publicly documents their security system and well known experts have given it their thumbs up, while another vendor says their system is secret and has sued people for attempting to reverse engineer it? Knowledgeable folk would have far more trust in the former than the latter.

dllthomas2• 2 years ago

a one time pad is and will remain highly secure

A one-time pad generated correctly and used correctly will remain highly secure, provided you have a highly secure means of sharing the key material. There's a lot rolled into those assumptions.

bawolff3• 2 years ago

At the same time "highly secure" is significantly underselling it. One time pads (if properly implemented) are information-theoretically secure. Even if you solve P=NP your one time pad will not be cracked. It is safe against an adversary with both infinite time and infinite compute.

That type of security comes at a cost.

Animats3• 2 years ago

There's a lot rolled into those assumptions.

Yes. No one seems to have mentioned VENONA.[1]

[1] https://en.wikipedia.org/wiki/Venona_project

pbronez• 2 years ago

A good example of #3 are public share links.

Things are more secure if you share your file with a specific set of users, but that requires your counterpart to have an account with the system you’re using (eg a Google Account for Google Drive). When sharing files with an arbitrary counterparty, it’s often sufficient to generate a publicly available, unlisted/unindexed, hard to guess URL. Even better if it’s time boxed.

I’m sure there are attackers who attempt to identify and enumerate these URLs. If they’re well designed though, it should be infeasible to guess the link.

walterbell2• 2 years ago

it’s often sufficient to generate a publicly available, unlisted/unindexed, hard to guess URL

Unless a service is leaking or spidering the URL into a public index.

https://positive.security/blog/urlscan-data-leaks

https://arstechnica.com/information-technology/2014/05/dropb...

https://security.stackexchange.com/questions/239762/how-are-...

avidiax• 2 years ago

https://gizmodo.com/cia-websites-reportedly-led-to-the-expos...

It is much harder than it would seem to keep these links secret. If one of your assets gets caught by other means, they could endanger the entire network if they use the same methodology.

The CIA thought they had a super great system, and then many of their assets got rolled up at once in a hugely embarrassing (and deadly) blunder.

matt_daemon• 2 years ago

This whole Technology Quarterly was terrifically written and researched for those wanting further reading: https://www.economist.com/technology-quarterly

They're all on the Internet Archive to read free, e.g. https://archive.md/Ed12X

BostonEnginerd• 2 years ago

Just a minor nitpick. To my knowledge, Archive.today is not known to be related to the Internet Archive (archive.org).

luuurker• 2 years ago

Yes, they're unrelated.

latexr• 2 years ago

I wouldn’t call it a minor nitpick. From the Internet Archive’s Wikipedia page:

The Internet Archive is an American nonprofit digital library founded in 1996 by Brewster Kahle.

https://en.wikipedia.org/wiki/Internet_Archive

In other words, it’s a legal entity and we know who’s behind it.

In contrast, we don’t even know who runs archive.today.

https://gyrovague.com/2023/08/05/archive-today-on-the-trail-...

knallfrosch4• 2 years ago

The Economist also offers a monthly subscription and some free trials. But honestly, they're simply worth their money.

setopt3• 2 years ago

Their content is great, but their subscription system is abhorrent. I’m not resubscribing in the future despite liking their content, and wouldn’t recommend that anyone else does either.

If you want to cancel your The Economist subscription, you can’t just click a button. You need to wait to talk to a sales rep in a chat room… when they arrive, they will basically beg you to stay; here’s a discount offer and here’s another, you’ve been a subscriber for X years why stop now. Only after insisting for 15min that you really want to cancel will they let you. I’ve gone through that process twice, and find it very off-putting.

kimi• 2 years ago

I used to be a subscriber for 20+ years, they are worth their money.

Why "used to", then? because a couple of years ago I could not basically find a way to have my paper version subscription renewed. I was literally not able to renew it! after a few "chats" with their sales reps, I gave up in frustration and discovered I can live without.

IIRC, thew wanted you to have the electronic version at all costs, while I'm happy with paper.

In any case, in an age of vapourware crappy SEO articles, they have a lot of meat, and a global world-view. It's the best way to spend money on news.

ikmckenz• 2 years ago

Is the Technology Quarterly available as a physical magazine I could buy anywhere? It’s not obvious what the best way to buy individual issues is.

1vuio0pswjnm7• 2 years ago

"Radio is more resilient than software."

StiffFreeze9• 2 years ago

Radio receivers have significant digital components which may leave more trail than the spy intends.

I like how some malware hides in plain sight and relays through google analytics.

knallfrosch4• 2 years ago

You could buy a cheap old radio at a pawn shop.

Animats3• 2 years ago

A cheap old radio will rebroadcast what you are listening to at the IF frequency.

az09mugen• 2 years ago

Security by obsolescence

weitendorf2• 2 years ago

Not really a good article. You can and should apply the exact same argument to number stations as you apply to all the technology they criticize: they are vulnerable to being compromised at the supply-chain/provenance level. I'm not a radio expert but I'm also pretty sure that you can interfere with their signals. And you can communicate using OTPs using a computer network as long as you're smart about it.

Actually the one interesting point made is that nobody can track whether you're tuning into a particular station. On a network, there has to be some traceable path of connections between the transmitter and receiver: even if the message is hidden in some other content or transmitted through a bunch of proxies, that traceable flow of data must exist. It makes me wonder how common it is to open ephemeral p2p connections over shortwave to transmit data between two computers - I'm sure someone's thought of it, and I think I brought it up one time during a quant firm system design interview.

rdtsc• 2 years ago

Actually the one interesting point made is that nobody can track whether you're tuning into a particular station

That’s a juicy enough piece of information that they probably have something for it. Does the radio emit any heterodyne signals when tuned to particular frequency? Maybe a super-sensitive satellite, drone or other sensors can pick it up.

Another option I could think of is to somehow infiltrate and compromise popular short wave radio models sold. Make them emit some signal marker which would identify the radio station it’s tuned to.

Pretty far fetched but the three letter agencies have spent money on crazier stuff than that in the past

weitendorf2• 2 years ago

My counter-counter-intelligence idea is that since you know where the radio broadcast station is, you can probably implement some kind of faraday cage with an aperture oriented towards the broadcast station. That way any kind of radiation emitted from the receiver also gets sent in that direction. That way detecting a signal emanating from the receiver requires being in the cone outside of that aperture (and I doubt those signals are so strong that they can be seen from space).

I'm sure your counter-counter-counter measures might start from the premise that, with you also knowing the location of the broadcast station, you might be able to guess at the most likely receiving orientations if you knew the most likely places for a receiver to be located. Eg a shortwave reciever equipped with a faraday cage + aperture listening to codes from Russia in Manhattan would emit a cone in the direction of Stamford. But I also suppose that I might know my receiver emits this kind of signal, and use some other device to emit junk signals that look similar, or scatter around a bunch of receivers while only using one.

Or I might try to only set up receivers in places where the cone would be inconvenient for you to intercept, or obvious that you were trying to intercept. Eg over the ocean.

a-dub2• 2 years ago

see also: the conet project. home recordings of numbers stations from around the world:

https://en.wikipedia.org/wiki/The_Conet_Project

audio now free on the internet archive:

https://archive.org/details/ird059

davidgerard• 2 years ago

https://archive.ph/b3WVn

roody15• 2 years ago

This article makes me think of an intercom system I maintain at one of our buildings. The fact that it is offline and each location is physically wired = it’s safe and secure. Another school district about 80 miles away had their systems hacked including phones, cameras and intercom .. as they were all meter and “cloud” based.

Just makes me rethink does everything thing need internet access. Sometimes perhaps simple safe and secure may fit better. Kind of off topic of this article but the concept just kind of got me thinking out loud.

midtake• 2 years ago

It depends on threat model. A wired intercom can be easily bugged with a physical implant. Discovering such a bug is also a completely different art from securing code, so different that some would claim it is more difficult to secure with any guarantee of confidentiality.

The cloud-based model might be leaky due to complexity but has the capability to deliver cryptographic assurance, which is a huge win in the long run. Modern cloud delivery is infamously insecure at the current point in time because most companies do not care about the security of their customers, and most customers are not aware of more secure options. But in the end as the technology matures it will be far more secure.

Of course, cutting off internet access is a good practice and most cloud connected systems play happily with a proxy.

MisterTea• 2 years ago

A wired intercom can be easily bugged with a physical implant.

I think the big impact here is that mundane systems which are now connected to the internet have become targets for remote vandalism or espionage.

notTooFarGone• 2 years ago

Yeah love those threat models where physical access is a topic but basic MFA measures are not even done. This is like comparing yourself to Fort Knox while not even locking your door.

Physical access is not a problem when basic other measures are not taken. If physical access is your largest threat then you already safer than 90% of companies imo.

Ajedi32• 2 years ago

Its possible to design internet connected systems that are secure and reliable. But usually "internet connected" means "dependent on continuous connectivity to some external service that needs to be actively maintained by a third party otherwise it'll stop working", which makes the "reliable" part difficult, and the fact that its exposed to a network with other devices on it and you have no way of knowing how competent that same third party is when it comes to security makes the "secure" part difficult.

Offline systems have way fewer failure modes such that they're often "secure and reliable" by just default, at least in comparison to the alternative.

olyjohn• 2 years ago

We're talking about an intercom in a school system. Why would they care about encryption or someone listening in? They probably just want to be able to talk to other people on campus, and not have it be taken over remotely by some script kiddie and turning it into a node in a botnet.

saurik• 2 years ago

Why should I need Internet/cloud to get something as basic as encryption?

hilux3• 2 years ago

I don't think it's off-topic at all!

Modern-day spying: sometimes old technology is more secure

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