Hunting for North Korean Fiber Optic Cables
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Delving into the mysterious world of North Korean internet infrastructure, a recent blog post sparked a lively discussion about the country's fiber optic cables and cybersecurity landscape. Commenters with firsthand experience hacking North Korean web infrastructure chimed in, sharing insights on the country's firewall configurations and exploit vulnerabilities. One surprising takeaway was that North Korea's limited IPv4 addresses aren't due to a lack of allocation, but rather a deliberate choice to restrict external accessibility. As commenters geeked out over the intricacies of North Korea's online presence, the conversation revealed a fascinating intersection of geopolitics and cybersecurity.
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A bit over a decade ago I used to spend a lot of time hacking North Korean web infrastructure, I mostly found that they tended to have firewalling around almost all boxes exposed to the global internet and usually had pretty impressive reaction times if you tried to access the country intranet through a compromised web server.
I've always wondered how successful NSA and the likes have been at infiltrating DPRK networks, as it would inherently be fairly easy to detect any sketchy traffic from the outside. I wonder if the recent NYT story essentially confirms that difficulty.
I guess I have a question after all: I'm not exactly clear on how NK treats end-user devices. Do you know if the endpoints used by NK based remote workers have internet and intranet access at the same time? If they do, such an endpoint could offer an easy and stealthy channel to access the intranet.
https://github.com/b30wulf/Malware-collection/blob/4f5906c93...
There was also the hacking team leak from years ago and they were selling exploits for north korea's red star OS: https://nkinternet.wordpress.com/wp-content/uploads/2025/12/...
I assume they've been on their networks in the past but i think North Korea has also done a lot over the years to secure their side. it used to be a lot easier when they left everything as an open directory and didn't realize what they were doing.
South Korean NIS was in fact a hacking team client, so it would make sense. Especially considering how terrible Red Star OS was at the time, a HT engineer could probably have whipped those up in a couple of days.
https://web.archive.org/web/20180302155452/http://english.yo...
>I assume they've been on their networks in the past but i think North Korea has also done a lot over the years to secure their side. it used to be a lot easier when they left everything as an open directory and didn't realize what they were doing.
I'm sure they've had some success, but I'd expect it to be a really difficult environment to operate in. Even for the NSA. I suppose eventually there'll be a better leak and we'll get to find out just how well it's been going.
Interesting document - confirming "everyone spies on everyone". Is this from some sort of corporate NSA chat room?
It's interesting to discover the reality that packet routing ends up following political affiliations. I didn't know North Korea only has 1,024 IPv4 addresses. Do you know why so few IPs? How did they get them?
As far as I know, end-user traffic from within North Korea usually does not originate from those few IP addresses. Or at least not visibly so, they might be connecting to a proxy from a DPRK IP address.
IP4 is quite limited as far as I know and not given out freely since a long time, or what do you mean here?
E.g. I was able to get a /24 in the ARIN region in 2021 and could justify 2 more for a _logical_ network topology similar to what NK presents to the world.
APNIC similarly has a pool available for IPv4 allocations: https://www.apnic.net/manage-ip/ipv4-exhaustion/#the-situati...
[1] as of Nov 2025, approximately 3 million or a little more than 12,000 /24s https://www.apnic.net/manage-ip/ipv4-exhaustion/#how-to-tras...
Certainly political affiliations have some influence, but also China and Russia have land borders with North Korea and are not at war. It's very common to run fiber optic on/under railroads and vehicle roads, so there you go. It's probably pretty hard to attract an international cable consortium to land in North Korea given everything, but terrestrial cabling is easier to start with anyway.
> I didn't know North Korea only has 1,024 IPv4 addresses. Do you know why so few IPs? How did they get them?
They would have asked APNIC, the Regional Internet address Registry for their region (Asia-Pacific). I can't find an assignment date, but 175/8 was assigned to APNIC in 2009. 2009 lines up with wikipedia reporting of the startup of the current ISP joint venture.
What's your source for that number? Is it GBit or GByte? Are they building out OTU1?
The last one is connected to the internet and this is why you can see (or at least before the pandemic could see) Instagram posts from North Korea.
I have no idea if this information is still or ever was completely true though.
There's a somewhat dated but very interesting AMA on Reddit by an American teaching computer science in Pyongyang:
https://www.reddit.com/r/IAmA/comments/1ucl11/iama_american_...
Reading about the internet knowledge possessed by North Korean students, I'm always surprised how they supposedly also manage to be some of the most cunning and evil actors when it comes to hacking.
America has penetrated most of the world and has nearly absolute control over digital systems. Keep that in mind when discussing cunning and evil actors.
If you're worried about "absolute control over digital systems", notice how many standards get published describing how those digital systems work -- you're welcome to reimplement them if you'd like more control.
why did they invest in those roads?
/s? This is literally a Monty Python sketch.
The Romans were true imperialists. They considered their opponents to be barbarians, and claimed they lived in wastelands. The truth is more complex. In many places — yes, including Judaea — they inherited infrastructure and buildings. Judaea was previously occupied by the Greeks and a number of other civilisations had left behind remains. The idea that it was terra nullis or a tabula rasa is nonsense. Even Gaul which was considered to be a frontier already had a road system (some of which has been only rediscovered in recent times), and what is now Marseilles was a Greek city going way back before the Roman conquest.
Romanes eunt domum indeed.
The Romans also aggressively appropriated and integrated the people they conquered, extending the concept of citizenship and thus what it meant to be Roman in the process.
Nobody is saying the Romans came across terra nullis. But describing their engineering and culture as "merely improving roads" is silly.
When I was growing up we were taught the Romans' own imperial myth that they had built upon nothing. The Monty Python film even promotes that as a joke. There are cities in the Holy Land like Jericho which were inhabited before Rome was even founded.
p.s. Do I get downvotes for pointing out archaeological and historical fact here?
They learned and appropriated. People and cultures that think anything foreign is evil don’t tend to advance.
The Romans weren’t some progressive legend. But they integrated and distributed knowledge and technology expertly, and were genuine innovators in their chief technology, that of scaled administration.
> When I was growing up we were taught the Romans' own imperial myth that they had built upon nothing
Why do you think this says anything about the Romans versus the context in which you were educated? Is there a single historical source from Republican, Imperial or Eastern Rome you can point to that claims Rome was built on nothing (other than the founding of Rome)?
They identified as conquerors. You don’t get a triumph for shooing some goats off a hill.
you may want to read this book about the military history of the internet originating in counter insurgency strategy in vietnam.
https://www.amazon.com/Surveillance-Valley-Military-History-...
another way to look at american internet penetration is as “radio free asia dot com”
I sort of suspect this is just the result of a nation state that is willing to be a pariah. That is, I think nearly any large state could do it if they didn't mind burning bridges.
The world doesnt make sense if you ignore history.
They probably hack for the same reason the west does it: attack/defense and money.
Does anyone remember LAPSUS$ https://en.wikipedia.org/wiki/Lapsus$ from a while back? It was reported for a while that it was largely made up of teenagers, and it seems two did get caught. I recall their whole MO being brazen social engineering/using stolen credentials in a way that got them caught pretty quickly, but also got results fast.
Crime being illegal doesn't prevent crime, but it adds an enormous amount of friction. In the West if you are decent at hacking, low-level APIs or reverse engineering you could turn to cyber crime. But if you instead get a regular job in cyber security or software engineering you still get a good salary, and don't have to worry about your online friends being police informants, can tell your potential significant other what you do to earn a living, get money wired directly to your bank account instead of having to go through costly intermediaries with significant risks, don't have trouble with the tax authority, etc.
If you reduce the legal opportunities and remove the downsides of the illegal ones the calculation completely changes, and with it the talent pool
If I told you today that I will pay you a million dollars to go fuck around with some North Korean servers, and doing it completely anonymously with the full protection and sanction of your government, would you say no?
I think you may have some unrealistic views on how North Korea operates internally. 99% of their population lives completely normal lives and has zero extra interactions with the government beyond basic grunt military service which is common across much of the world, and paperwork for licensing, permits, and taxes. We only see the worst possible views of North Korea from the outside, slathered with thick layers of additional propaganda on top of it.
If you consider numerous reports of people that managed to barely escape and report this consistently in the west as pure propaganda, thats... your paranoid mindset. Sometimes people and regimes are simply evil, 21st century is in no way immune to that.
>Ahn noted that prisoners detained in the punishment chambers were often crippled after three months and dead within five months. Ahn and other former guards have testified to the brutality that they were encouraged to demonstrate while punishing prisoners. Former guards have confessed that they were taught not to view prisoners as humans. However, the number of deaths from beating prisoners was so high that at one point, the guards were encouraged to be less violent. https://www.state.gov/wp-content/uploads/2019/03/Prisons-of-...
>One inmate recalls that as a 10-year-old he was told to lift a 30kg sack of earth (more than his own body weight) 30 times a day. If he slipped he was beaten with sticks by his teachers. Kang Cheol-hwan (former Yodok inmate. He was detained with family as a young boy). Here called: The work was too much for me or for any child of my age. But I did not dare to complain. After the first ten rounds, my legs started shaking, my body was hurting and my shoulder skin was peeling off. I was near collapse but the teachers were watching us and beating us with sticks if we stopped.”
>Kang Cheol-hwan also recalls deaths of children who were working at a work site. “The children in my class were ordered to dig and move earth to a work site 200 metres away. Twelve children dug holes with shovels and the other children carried the dirt in sacks or buckets. The dig site was a clay hill and the clay was quite soft. But we were afraid that as we dug deeper, it could collapse at any time. The teachers who were supervising us told the children to keep digging. After three days, the hill suddenly collapsed. There were six children who were on top of the hill when it collapsed. Three children were killed and the other three were badly injured. However, the teachers blamed the children for the carelessness.”
>Between the ages of 13 and 16, Shin recalled: “I was forced to undertake dangerous work and saw many children killed in work. Sometimes, four to five children were killed in a day. On one occasion, I saw eight people killed by an accident. Three men were working high up on a tall cement wall, three 15-year-old girls and two boys were helping them with mortar below. I was carrying mortar to the children when I saw the cement wall falling. Eight were buried under many tons of mortar; there was no rescue. Instead, the security officers told us not to stop work.” https://www.amnesty.org/en/wp-content/uploads/2021/07/asa240...
>Security officials armed with machine guns gathered together all the political prisoners at the camp to witness the hanging of the two adults and the execution by firing squad of the three children.
>“Interviews were conducted with 35 defectors who had escaped from various detention facilities in the preceding 18-month period, and 31 of them testified to having witnessed the killing of newborns.” https://web.archive.org/web/20141006072142/https://www.kinu....
If you only met the world on American TV, yes.
This sentiment is probably overblown. The fact that they are effectively robbing people to earn some money for their pathetic regime means only that they are on the level of nowadays internet scammers. They are good at that too.
Spending enough money (and they spend a lot - 26 million people work only for this) one can train people to do this or hire people to do this for them.
I do not think that exists. I imagine the diplomats and other foreigners living there will have this, though.
When I was there two times (in Pyongyang, and in villages in the north east & Rason) any access to the outside world was prohibited via a network other than telephone (I could make outgoing phone calls via the hotel). Even traveling very close to the border (which they use jammers to block outside connections), my guides were annoyed when they saw I was trying to connect to the Chinese network from my phone.
The only place I saw any access "to the outside world" was in Rason (https://en.wikipedia.org/wiki/Rason_Special_Economic_Zone), where one of the casinos had a computer which could be used to access the internet (through the Chinese GFW, of course).
Like I have fiber to the house and you really need to pinch it and whatnot to cause an internet outage.
A large bend radius means it has to be a big bend.
A 7.5mm bend radius is really small. You can bend that stuff pretty tight before you create a problem.
https://www.seeclearfield.com/fiber-optic-wall-box/metal-wal...
As for utility boxes along the track, it could be something railway-related, for example, some railway control or monitoring equipment.
What's the most important piece of camping gear you can take with you?
A meter or so of fiber optical cable. So that if you get lost of injured you can bury it and wait for the backhoe to show up and dig through it, then get a ride back to civilisation with the operator.
Also, installing general telco fibre next to railway lines is standard practice. Makes all the bureaucracy so much easier if you can just use the existing railway right-of-way. Not that the DPRK would care much about right-of-way ;D
Some Hacker News threads are on their own level.
USA dropping nukes probably would have been the better outcome for humanity.
I'm far from convinced that using nukes in the Korean War would've been a good move, but equating it with "kill[ing] them all" is completely dishonest. What's your goal in this debate, and is it served by dishonest rhetoric?
The US nearly lost the Korean war.
The US army was nearly overrun at least once.
The US airforce never achieved air superiority, and Soviet aircraft were better in most ways.
The only undisputed advantage the US had was nukes, which is why MacArthur wanted to use them tactically (!)
The only path that America had to win in Vietnam was to destroy it, including the population they were allegedly there to protect. Hence they lost.
If you exclude the outliers like Campuchia and Nazi Germany, even the most benign commies are always way more deadly than the most ferocious fascists.
Unification was supported by both sides among the people, most South Koreans supported communism and 70% of them supported unification with the North. South Koreans didn't even support their own government, they were dealing with internal insurrection from their own people. The North was an industrialized nation and the South was a poor farming country and their unification would of been hugely beneficial to both. The war would have been over in another 2 weeks without intervention and a minimal amount of casualties, and it had only been 3 months from the start of the invasion. The only people not in support of it at the time was the political leaders of SK at the time because it meant they personally as individuals would lose power and wealth, and the US who was on a crusade to crush and kill anybody who dared support communism. Korea never should have been split in the first place, but the US and USSR had to be little bitches and force their will upon these people.
Killing 5 million people, most of which were innocent civilians, in the name of "fighting communism" is evil, not the idea of a unified nation of people supported by those same people.
Soviet occupation. Korea was supposed to be unified and elect a government back in 1950, Soviets made sure it didn't happen because they had no chance of winning.
That and, you know, the whole invasion thing.
Pretty sure the soviets were perfectly fine with the North taking the South considering the South was US aligned which gave the US a foothold right on their doorstep. And again, the vast majority of Korean people on both sides supported Korean unification. The South Korean leadership, which was basically appointed by the US for their pro-US and anti-communism stance, was so unpopular among South Koreans that there was civilian insurrectionists trying to topple it. The South Korean military upon invasion couldn't even keep its own troops from deserting in significant numbers, and they even blew up a bridge full of refuges to try and stop the advance which it failed to do.
Yes the North invaded which is generally bad, but they did do it with popular sentiment among the people, and they weren't attacking and killing civilians along the way.
And regardless of all that, none of that justifies the US response of bombing and killing millions of civilians and leveling entire cities. The Korean War is considered the most deadly war in Asia ever, and had far higher percentage of civilian casualties than WWII and Vietnam.
I guess if I have to explain it I might as well not bother.
The entire analysis of capitalism which articulated the class system with which it replaced that of the pre-existing aristocracy and revealed the elimination of class to actually just be a switch in its structure and elevation of a new ruling class was by Communists.
NK is paranoid for very valid reasons.
Sure it was a correct thing for Kims to do, millions of Koreans be damned.
You seem to have... very strong while also contrarian opinions in this thread to be polite, leaning heavily into apologist position for North Korean government
Why in that country ? US controls much of western opinion and made a lot of atrocities, yet, nobody cares (see the ongoing https://en.wikipedia.org/wiki/2025_United_States_military_st... )
I can't even say that they made the wrong decision either, North Korea still exists as an independent nation which is amazing in itself.
America bombed North Korea back to the stone age. Now we in the West wonder why it’s so F’d up by its very own volition.
[1]: This is not to say that North Korean propaganda is not real.
North Korea is responsible for adding the hot beverage, umbrella with raindrops, and lightning bolt emojis
https://en.wikipedia.org/wiki/KPS_9566
also a ditch witch and couple of support vehicles could run cable through most terrain, and in agrairian areas , not needing permits and such, would be indistinguisashable from other activity ,happen very quickly, and leave no trace
humanity has reached the point where our comunications net is a given for 90%+ of the population centers in one form or another, and if not for the slop, would have an order of magnitude, excess capacity. throw in peer to peer ,and the soon to be blanket coverage from sattelite swarms, and well, what? sonar relays for underwater, and seizmo transmitters
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