kristoff

@kristoff@infosec.pub
7 Post – 63 Comments
Joined 1 years ago

This is a typical mail a phishing campaign would send out, and we have already said to people "never believe this kind of messages. They are all fake.

Now, if a genuine company sends out mails with a genuine gift-cards (what the article on techcrunch seems to indicate) .. this is NOT helpfull at all!!!

And that comming from a cybersecurity company (rolling-eyes)

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Hmmm .. 🤔 The best way not to make friends with somebody with over 30 years of coding experience: suggest him to use ChatGPT to write a computerprogram 🤣🤣

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Wauw! So many answers in such a short time. Thanks all! 👍 (I will not spam the channel by sending a thank you to all but this is really greatly apriciated)

Concerning ncurses. I did hear of it but never looked at it myself. What is not completely clear for me. I know you can use it for 'low-level' things, but does it also include 'high-level' concepts like windows, input fields and so?

The blog mentioned in one of the other posts only shows low-level things.

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ah. That looks very interesting. And they have a show here in the EU, and it seems to work with gadgetbridge (thx Lambda RX :-))

Thanks!

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Hi,

What is the reason you do not want a domain? it is not that DNS-domains are that expensive these days. The cheapest option I found is .ovh (which is one of the major cloud-providers in France), which is 3 euro / year (+VAT). You can then put as much hosts or subdomains under it, and it supports dynamic IP.

Agreed, .ovh is not the most "professional" looking domain, but it depends on what you want to do. If your goal is simply to have something for yourself / family / friends, then this is good enough.

BTW. Having your own domain for a nextcloud instance has additional advances: you can get a real https/tls certificate from letsencrypt, and -if you put a reverse proxy in front of your NC- it shields you from people who just scan the complete IP-space of the internet but who do not know your domain.

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just out of interest .. somebody here on satellite? I am interested to know the prices for sat services out there?

I dan't know if this is still valid but I used to be told to have different partitions for your system, logs and data (home directories) .. and have the swap-partition located in between them. This was to limit the distance the head has to move when reading from your system starts swapping.

But if you use a SSD drive, that is not valid anymore of course :-)

Kr.

or a one-way trip from a window on the 10th storey of a building all the way down to the ground.

Yes. Fair point.

On the other hand, most of the disaster senarios you mention are solved by geographic redundancy: set up your backup // DRS storage in a datacenter far away from the primary service. A scenario where all services,in all datacenters managed by a could-provider are impacted is probably new.

It is something that, considering the current geopolical situation we are now it, -and that I assume will only become worse- that we should better keep in the back of our mind.

Well, the issue here is that your backup may be physically in a different location (which you can ask to host your S3 backup storage in a different datacenter then the VMs), if the servers themselfs on which the service (VMs or S3) is hosted is managed by the same technical entity, then a ransomware attack on that company can affect both services.

So, get S3 storage for your backups from a completely different company?

I just wonder to what degree this will impact the bandwidth-usage of your VM if -say- you do a complete backup of your every day to a host that will be comsidered as "of-premises"

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As a sidenote. This reminds me of a discussion I haver every so often on "tools that make things to easy".

There is something I call "the arduino effect:. People who write code for things, based on example-code they find left and right, and all kind of libraries they mix together. It all works .. for as long as it works. The problem is what happens if things do not work.

I once helped out somebody who had an issue with a simple project: he: "I don't understand it. I have this sensor, and this library.. and it works. Then I have this 433 MHz radio-module with that library and that also works. But when I use them together. It doesn't work"| me: what have you tried? he: well, looked at the libraries. They all are all. Reinstalled all the software. It's that neither me: could it be that these two boards use the same hardware interrupt or the same timer he: the what ???

I see simular issues with other platforms. GNU Radio is a another nice example. People mix blocks without knowing what exactly they do.

As said, this is all very nice, as long as it works

I wonder if programming-code generated by LLMs will not result in the same kind of problems. people who do not have the background knowledge needed to troubleshoot issues once problems become more complex.

(Just a thought / question .. not an assumpion)

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What was that saying again?

"the biggest thread to the safety and cybersecurity of the citizens of a country ... are managers who think that cybersecurity is just a number on an exellsheet"

(I don't know where I read this, but I think it really hits the nail on the head)

The issue is not cloud vs self-hosted. The question is "who has technical control over all the servers involved". If you would home-host a server and have a backup of that a network of your friend, if your username / password pops up on a infostealer-website, you will be equaly in problem!

A /48 is quite overkill for a home customer. Do you have 65536 LANs at home? Here in Belgium, we get a /56.

Protection of citizens against unjust ruling by a court is a protection-principle of democrary.

Why would you grant such a protection to an organisation aimed at destroying democracy (X/twitter)?

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OK. That makes a lot more sense.

Thank you for correcting the original post. 👍

Big international companies have no problem to create pseudo "national" versions of services if they can make more money with it.

So there should not be a problem for the social media companies to create versions that meets local legislation.

If you create a product and want to sell it in a certain market, you must also adhere to the laws of that country/region.

The question is .. do we care about THAT 80 % of the people. I would be more then happy if we can have that 20 % of more technical-oriented audience :-)

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A URL 'Free up to some-end-date'. ???

Phishing link? 🤔

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To be honest, I have no personal experience with LLM (kind of boring, if you ask me). I know do have two collegues at work who tried them. One -who has very basic coding skills (dixit himself) - is very happy. The other -who has much more coding experience- says that his test show they are only good at very basic problems. Once things become more complex, they fail very quickly.

I just fear that, the result could be that -if LLMs can be used to provide same code of any project- open-source project will spend even less time writing documentation ("the boring work")

Hi,

I have also been thinking about selfhoating a jisti-meet server. Just how easy / difficult is it to selfhost it? Do you run it in docker or natively? Linux or some other OS (FreeBSD)?

Kr.

Concerning linux, yesterday I was watching this video on computerphile on the crowdstrike incident. https://www.youtube.com/watch?v=rlaNMJeA1EA (*)

What is interesting is the comment made in the video on how chromebooks do software upgrades with dual "OS" disk-partitions and the ability to rollback to the previous OS-partition.

Question: is something like this also possible on one of the major linux distros? (debian, ubuntu, rocky, ...) What would be the procedure to do this kind of "dual partition" system-upgrade?

(*) a great video that explained some of the technical details in a very clear way, including some very interesting 'lessons learned' and "what if"s If you ever need to explain crowdstrike to your manager, this video is a good start.

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Australia looks like an interesting case. Iknow that in some countries, ISPs have to provide service to both urban and rural customers at the same price, which means that urban customers actually subsidize people living in rural areas. In some other cases, the gouvernements help pay for this.

Isn't there a project in Australia that the federal gouvernement is subsidizing the role-out of fibre?

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Hi, Perhaps a stupid question, but what exactly is required to port an OS to a different architecture? OK, there is the boot-process, and low-level language compilers, ... but what else?

How much code has actually to be rewriten, and how much just needs "make" to be recompiled?

Kr.

Hi Neutrom, I don't know this one. I'll check it out. Thx! 👍

Hi, I have it running as of today. apache reverse-proxy native on the server and "stable-8922" in docker.

I have been wondering if it makes sense to move the jvb from docker to the server. I guess that is the part of the system that pulls most of the traffic. I don't know if this make any real difference for performance or not.

Anycase. All, thanks again for the help. Appriciate it. :-)

Kr.

for the nextcloud instance on my local LAN , I use the .local domain (multicast DNS). Just enable avahi on your server and you can use hostname.local on your network without having to deal with local DNS on your router and so on.

For me, the first goal is to simply understand the setup. I now have been able to create a setup with two frontend jvb-instances and one backend. In the end, the architecture setup of a jitsi-server is quite nicely explained, and -by delving a little bit into the startup scripts of the docker-based jitsi setup, you do get some idea of how things fit together.

From a practicle point of view, I think I'll go for the basic setup (1 backend, 2 frontends) natively on two servers, and -if the backend server would go down- just have a dockerised backup-setup ready to go if it would be needed.

Thanks!

First of all, thanks to all who replied! I didn't think there would have been that many people who self-host a SSO-server, so I am happy to see these replies.

As a side-note, I have also been looking into making the setup more robust, i.e. add redundancy. For a "light redundant" senario (not fully automatic, but -say- where I have a 2nd instance ready to run, so I just need to adapt the DNS-record if it is needed), can I conclude from the "makeing a backup" question, that I just need to run a 2nd instance of postgres and do streaming-replication from the main instance to the backup-instance ?

Or are there other caviats I haven't thought about?

In this case, it is not you -as a customer- that gets hacked, but it was the cloud-company itself. The randomware-gang encrypted the disks on server level, which impacted all the customers on every server of the cloud-provider.

I have been thinking the same thing.

I have been looking into a way to copy files from our servers to our S3 backup-storage, without having the access-keys stored on the server. (as I think we can assume that will be one of the first thing the ransomware toolkits will be looking for).

Perhaps a script on a remote machine that initiate a ssh to the server and does a "s3cmd cp" with the keys entered from stdin ? Sofar, I have not found how to do this.

Does anybody know if this is possible?

Well, based on advice of Samsy, take a backup of home-server network to a NAS on your home-network. (I do home that your server-segment and your home-segment are two seperated networks, no?) Or better, set up your NAS at a friend's house (and require MFA or a hardware security-key to access it remotely)

Yes, that was indeed the question.

If I read it correct, you need a specialised distro for this. You cannot do this on a off-the-shelf Debian or Ubuntu?

I'll do some searching on 'unmutable Linux'. Thanks for the (very quick) answer! 😀

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Hi,

Just to put things into perspective.

Well, this example dates from some years ago, before LLMs and ChatGPT. But I agree that the principle is the same. (an that was exactly my point).

If you analyse this. The error the person made was that he assumed an arduino to be like a PC, .. while it is not. An arduino is a microcontroller. The difference is that a microcontroller has resources that are limited: pins, hardware interrups, timers, .. An addition, pins can be reconfigured for different functions (GPIO, UART, SPI, I2C, PWM, ...) Also, a microcontroller of the arduino-class does not run a RTOS, so is coded in "baremetal". And as there is no operating-system that does resource-management for you, you have to do it the application.

And that was the problem: Although resource-management is responsability of the application-programmer, the arduino environment has largly pushed that off the libraries. The libraries configure the ports in the correct mode, set up timers and interrupts, configure I/O devices, ...And in the end, this is where things went wrong. So, in essence, what happened is the programmer made assumption based on the illusion created by the libraries: writing application on arduino is just like using a library on a unix-box. (which is not correct)

That is why I have become carefull to promote tools that make things to easy, that are to good at hiding the complexity of things. Unless they are really dummy-proof after years and decades of use, you have to be very carefull not to create assumptions that are simply not true.

I am not saying LLMs are by definition bad. I am just careful about the assumptions they can create.

I will put "multicloud" on my wishlist.

Looking at it from a infosec point of view, cloud-providers are an ideal target. All the customers who have just lost all their data now complaining to the cloud-provider are the ideal pressure-mechanism to get the cloud-provider to pay out.

I don't. I thought the emoji would have made that clear.

I have been doing cybersecurity awareness lately. We are starting to get over the furst hurdle: make people see the signatures of phishing message. But now we are starting with the 2nd hurdle: make people understand that when they write a genuine post, they should avoid these signatures of phishing, in this case, the "time pressure" argument.

The problem is that the more genuine messages have phising signatures, to more difficult it becomes for people to distinguish a genuine posts from phishing. There is also the risk that you genuine posts will get noted as fake (although that is clearly not the case here :-) )

Hi,

Good idea!

And once you have you domainname, you can do the following:

  • set up a reverse reverse proxy (apache, nginx) in front of nextcloud
  • in the configuration of apache/bginx use virtual hosts.
  • make sure that the default virtualhost (in apache, that is the the one that does not have "ServerName") first in the configuration. Point that to a local website with just an empty directory
  • then, AFTER the default virtual host, add the reverse-proxy configuration of your nextcloud instance.

What this does, is that if somebody addresses your website with a URL that does not contain the exact hostname of your nextcloud, the webquery will go to the empty website and simply return a 404. A hacker who does a webrequest to "https://your-ip-address/login" will just get a "404 not found" and not reach your nextcloud instance.

This keeps people who just scan the internet for vulnerable systems and try out all kind of URLs to try to get in out of your nextcloud.

Of course, this only works if you keep the full hostname of your instance to yourself and do not post it somewhere (including social media, mailing-lists, ...)

Good luck with your nextcloud server

One of the reasons I am looking for a new sportswatch is because I try to reduce my smartphone use and I noticed that I actually took out my smartphone just to check the time.

I have an old garmin vivosmart HR but I do have a problem with the charging cable. Plus I am not able to download the healthstats with my linux 'daily driver' laptop.

Perhaps I should just get a cheap regular watch somewhere? 🤔

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What is your 'deleted files' policy? How long do you keep them? I had a similar issue but then found out that the nextcloud cron-process wasn't running so files in the 'deleted files' folder where never really deleted.

If you get your domain from OVH, you get one single mailbox (be it with a lot of aliases, like a different email-address for every service/website you use) for free.