Comments
By Doohickey-d 2025-06-1618:095 reply This is actually quite common: I've been on ferries, at airports, even hotels, which give you some amount of time for free, often anonymously. So just a mac address change gives extra internet.
New Android versions make it especially convenient, with a "Wi-Fi non-persistent MAC randomization" option in the developer options, meaning you can just "forget" the wifi network and connect again with a fresh mac address.
In some cases I've seen networks that allow any traffic on port 53 - it doesn't have to be DNS traffic. The most surprising one was a mobile network with a pay as you go payment model: load money first, buy a data package, when the data package runs out, you get a captive portal that says "you've run out of data" - but port 53 wasn't blocked, so a commercial VPN resulted in unlimited internet at unlimited speed, with roaming anywhere in the world (and that was back in the day before SIM card registration was required too, so anonymous, too).
> port 53
I haven't needed it for... probably 15 years, but in the past (before 3G was common, and all you could rely on was WiFi hotspots) I have used iodine[0] as an IP over DNS tunnel.
My uni friends were always impressed, and it really helped me a few times. The throughput was never great though, but enough for some basic browsing.
Edit you have to be prepared ahead of time though, and it's the main reason I bought my three-letter domain back then (shorter domain means higher throughput as payload is a higher percent of the query response).
By ipdashc 2025-06-1619:48 I still find uses for iodine sometimes! Off the top of my head, a hotel basement with no cell service, and once on a flight. It's rare that it works, but quite entertaining when it does.
I think in one of those two (forget which), they just had udp/53 wide open (which works just like any VPN), but in the other, it had to do proper DNS tunneling. And to my surprise, it was entirely fast enough to be usable, which usually is not the case. I felt bad for probably bogging down their DNS server, but hey. (Kept it to a reasonable limit.)
By rahimnathwani 2025-06-1618:42
The comment to which you replied was talking about networks where port 53 is open. But, given you were using iodide and you got slow throughout, I'm assuming you were on networks which blocked port 53 access to hosts on the internet, but allowed unlimited access to the ISP's own DNS server.throughput was never great though
By McAlpine5892 2025-06-1618:201 reply > but port 53 wasn't blocked, so a commercial VPN resulted in unlimited internet
The VPN would have to accept a connection over 53 though, right? This also seems like a great way to possibly bypass VPN blocking via DPI, which I've been hit with before on airlines when going over 443.
Yeah, but it doesn't cost much to accept connections on all ports (AIM did it in the 90s).
DPI should be able to easily detect and block non-DNS traffic on port 53, as well as IP over DNS. Just a matter of configuration effort; but lots of networks lack configuration effort, so it's worth a try.
By sandworm101 2025-06-1619:141 reply 5190 continued well into the 2000s.
5190 was the default port, but if it wasn't open, any other port would work. You could have the client do a scan to try ports until one worked.
By ethbr1 2025-06-1621:47 It'd be fascinating to get an at-scale timeline of ports blocked from common client connection points.
I assume it's drifted over time, but couldn't guess which ways / why. (Other than converging on blocking all non-443)
I think, in 2025 you are better off with this
Often forbidden on cruise ships as it would be on flights for the same reasons (possible interference). In an airplane it's also impossible to make it work though those tiny windows of course. But on a cruise ship balcony it would probably be fine.
By WorldMaker 2025-06-1621:051 reply It's also increasingly forbidden on cruise ships because their internet is today Starlink powered as well and additional Starlink receivers in the area are direct competition for bandwidth from the same satellites at the same time, and a cruise ship full of wifi-using passengers wants all the bandwidth it can get, in theory competition makes things worse for everyone, even the person with a personal Starlink receiver competing against the bandwidth flood of a cruise ship.
By ethbr1 2025-06-1621:49 Semi-related, does anyone know what Starlink uses for de-congestion negotiation?
By EE84M3i 2025-06-171:33 Also prohibited on US navy littoral combat ships
https://www.navytimes.com/news/your-navy/2024/09/03/how-navy...
By margalabargala 2025-06-1620:302 reply The rea$on that it i$ forbidden on crui$e $hip$ i$ not due to interference, whatever the company may claim.
By miyuru 2025-06-1619:11 My ISP had a captive portal to show when the connection was disconnected and had 1.1.1.1 whitelisted on all ports for some reason.
Back then the CF did not restrict the IP for quad 1 IP, so I could access any CF enabled site without any charges.
I imagine one of the ships officers will be tipped off by the IT team about the unusual number of free-internet activation attached to your booking id, and either give your room a visit to knock it off, or just bill some multiple of the $170 anyway.
It sounds like it should only be used only a few times per booking, and this is going to hit at least 4/hour for multiple hours a day, so it will stick out like a sore thumb in the logs ....
But, a cool hack, nonetheless :)
By JumpCrisscross 2025-06-1618:014 reply > imagine one of the ships officers will be tipped off by the IT team
If it’s any of the major cruise lines there almost certainly isn’t anyone in IT paying that much attention.
Yea, I'd think something like onboard Internet is something set up once for the ship, and then basically forgotten about as long as the overall revenue is above some "reasonable" threshold given the number of passengers. Ain't no security team sitting there monitoring user registration metrics in real-time looking for fraud. At best, they might pull logs every quarter to look for vulnerabilities like this to close.
By sodafountan 2025-06-1621:261 reply I haven't been on a cruise in a long time, does anyone know if there are on-board IT people? Might be an interesting job if I ever get bored again.
By noboostforyou 2025-06-1622:12 I was on a somewhat fancy cruise a short while ago (Celebrity, fwiw) and they had a small live tv production crew that would film around the ship broadcast daily events and stuff on the ship's tv channel. The live shows also had a number of a/v tech crew people so there certainly are some IT folks employed on the ships while it embarks.
Why would someone in corporate IT responsible for this not ask Claude to write a script that does this on a much more frequent basis? That person might get a nice attaboi for it, but much less likely an actual bonus for it. Although, I can't imagine they are losing too much money on each cruise from this hack unless the next DefCon is on a cruise ship. Then realizing that 0 passengers signed up for WiFi might seem strange
By JumpCrisscross 2025-06-1619:581 reply > Why would someone in corporate IT responsible for this not ask Claude to write a script that does this on a much more frequent basis
Because they have nine trillion bugs in their booking system that have been on backlog since 1910.
According to this source [1] (of dubious quality, granted) Royal Caribbean's entire IT department is about 140 people headed by an electrical engineer.
[1] https://rocketreach.co/royal-caribbean-cruises-ltd-it-depart...
That's even more reason to have LLMs do their work for them, not less.
By JumpCrisscross 2025-06-1621:21 > more reason to have LLMs do their work for them, not less
Nobody argued for or against LLMs. Just that IT isn't a major investment for any cruise line. And that fixing a problem like this isn't even rationally high on a cruise liner's list of priorities.
If the payment portal is bugging out and the engineer tasked to fixing it is off vibe coding on the off chance that a high schooler is using too much internet (versus trying to steal mom and dad's drinks), I'm not sure I'm unsympathetic to the manager's very predictable reaction.
Break things, break fast, break more, break the rest of it, keep breaking... What was the catchphrase? Breaking things doesn't help broken systems.
what exactly would this be breaking? it's an analysis of logs, not providing access to services.
By JumpCrisscross 2025-06-1621:241 reply > what exactly would this be breaking?
Whatever those nine trillion bugs the developer is supposed to be working on are up to.
By dylan604 2025-06-1622:07 they're clearly not fixing those either, so yet again, what's being broken that wasn't already broken?
Since the cruise ship is named, there is a good chance someone at the company (even without technical skills) will notice this article and tip off IT this way.
By paulpauper 2025-06-1618:49 This is why things stop working. they go viral and then get patched soon after
By maerF0x0 2025-06-1621:32 > If it’s any of the major cruise lines there almost certainly isn’t anyone in IT paying that much attention.
Until everyone is doing it and their revenue stream falls off.
By duxup 2025-06-1618:35 They probably have some paper pasted next to the equipment to look if the blinky lights are doing the thing, and how to power cycle things.
By kccqzy 2025-06-1618:33 I imagine the ship officers don't even understand how the internet on the ship works, much less detect fraud. Perhaps all they have is a button to restart the system in case someone complains it's not working.
> the unusual number of free-internet activation attached to your booking id, and either give your room a visit to knock it off
Cruise lines want happy customers. They aren’t going to do something to piss you off for $170.
By victorbjorklund 2025-06-1618:47 Not sure. They are known to confiscate for example starlink etc.
By keyringlight 2025-06-1622:10 I'd wonder what the costs and risks are of trying to get that $170, assuming it's one or a tiny amount of passengers compared to dozens each sailing who tell their friends. If you get someone who's got nothing better to do than argue on the topic, make you prove that the charge is justified and not just some misconfigured device that "didn't go online because I only use it for reading ebooks, honest", then it could get ugly including legal or press routes.
On a small scale for a cruise liner scaled operation I'd be prepared to say "huh, that's odd" or turn a blind eye to just one.
By shrubble 2025-06-1620:45 They likely have a canned solution like the Cisco Meraki or similar setup and are not looking for extra work; whatever they have is seen as in the category of set-and-forget.
If I was going to go on a cruise, I'd probably bring with my linux laptop for capturing WPA handshakes, and then use the 15 minutes to set up jobs for Hashcat to burn through on my gaming PC at home.
There is A LOT of AP's on cruise ships. Odds are a few are crackable.
If I were going on a cruise, I could think of many much better use of my time than cracking APs. This just seems like you're doing cruising wrong if you're so concerned about it that this is where you want to take your experience
By exhilaration 2025-06-1619:561 reply Sir, this is Hacker News.
Well, I don't hack wifi networks as part of my day job.
I'm an older dude, and no longer find talking to strangers all that fun.
I like nature and the outdoors, but that can be admired only from a great distance until you make port. Going fishing off a moving cruise ship will end your vacation rather quickly (aside from not being feasible - you're going too fast for anything which is catchable on light tackle).
I love the swimming pools and such, but my wife can't swim.
There's all kinds of gambling and stuff, but I don't gamble.
I spent much of the cruise wishing for better internet... Or that I'd brought more books.
We spent a good amount of time playing FF7 in the evenings on our hotel TV wired up to a PSP.
By dylan604 2025-06-1622:06 clearly, we're all free to do whatever for our precious time off, but you just listed a whole lot of things that you don't like to do yet you paid for it anyways. again, we all like different things, but i'd prefer to spend money doing things I enjoy, but you do you
By bearsyankees 2025-06-1618:002 reply Nice tool for curl -> python requests without an LLM, all static:
By yegle 2025-06-1619:43 Also `curl --libcurl curl.c https://example.com` to "convert curl to C code" :-)
By _gtuv 2025-06-1618:04 [dead]
