TM Signal
from root@lemmy.world to privacy@lemmy.ml on 08 May 01:28
https://lemmy.world/post/29299845

The scariest part of this recent news is that TM Signal seem(ed) to be interoperable. People using TM Signal could interact with actual Signal users. How are you to know whether or not your groups have people using bastardized versions of Signal? Are things like Session interoperable with Signal?

#privacy

threaded - newest

catloaf@lemm.ee on 08 May 01:34 next collapse

No. Even if they were, the are plenty of ways to capture the messages.

root@lemmy.world on 08 May 02:56 collapse

Definitely. Capturing the messages isn’t my concern though as much as interacting with non authentic clients

milicent_bystandr@lemm.ee on 08 May 03:52 collapse

What is your worry about non authentic clients?

root@lemmy.world on 08 May 06:54 collapse

Poor security implementations that would become the weakest link in the security chain

krolden@lemmy.ml on 08 May 01:35 next collapse

Any signal conversation can be archived

SomeAmateur@sh.itjust.works on 08 May 01:37 next collapse

I’m out of the loop what’s going on?

MoonlightFox@lemmy.world on 08 May 02:12 next collapse

Some photographer took a picture of a politician in the Trump admin using a Signal clone. That signal clone allowed the user to archive chats to a third party.

SomeAmateur@sh.itjust.works on 08 May 03:57 collapse

Thanks, that’s…interesting. He doesn’t seem like the type to find and try obscure apps for fun

utopiah@lemmy.ml on 09 May 10:35 collapse
AmbiguousProps@lemmy.today on 08 May 01:40 next collapse

In no way does Signal prevent conversations from being archived. For all you know, a recipient could be screenshotting all of your messages, and they could even be using the official app when doing so.

If you don’t trust your contacts, probably shouldn’t be messaging them anything sensitive.

root@lemmy.world on 08 May 02:55 collapse

Yes of course. Signal can archive messages and they can be restored, you can screenshot messages and you can have them backed up as part of a policy like icloud backups.

My question is more about how do you know you’re interacting with an authentic signal client, and not a bastardized one.

mp3@lemmy.ca on 08 May 03:44 next collapse

At the moment you can’t. The only realistic way I could see that happening is the the server would check the app digital signature and refuse the app from communicating with the official infrastructure if it didn’t match.

jesse@sh.itjust.works on 08 May 04:20 next collapse

Even then, nothing stops the client from lying to the server.

mp3@lemmy.ca on 08 May 04:29 collapse

That’s the point of digitally signing the app, to ensure its authenticity and integrity. TM and others wouldn’t be able to resign the modified app with the Signal Foundation signature.

EDIT: Yeah after thinking more about it it’s not a trivial problem, as you need to assume that the endpoint is inherently untrusted.

Corngood@lemmy.ml on 08 May 05:29 collapse

It’s actually possible in a way:

en.m.wikipedia.org/wiki/SafetyNet

But you necessarily need to limit the devices and operating systems that are allowed. No custom ROMs, no root access, etc.

It’s bullshit and breaks open computing as a concept.

ouch@lemmy.world on 08 May 22:06 next collapse

Fuck Safetynet and Play Integrity.

utopiah@lemmy.ml on 09 May 10:34 next collapse

Isn’t that just delegating trust to a third party, e.g. here Google? It’s not as if Google was somehow immune to 0 days.

EngineerGaming@feddit.nl on 10 May 08:04 collapse

Not to mention that a device that would pass Play Integrity is precisely the device I wouldn’t ever consider doing anything private on. Which would defeat the whole point of Signal. It’s already bad enough that it’s so desktop-unfriendly while much fewer phones than computers that can run non-privacy-invasive OSes than computers…

EngineerGaming@feddit.nl on 08 May 07:29 collapse

Which would be absolutely disgusting given that Signal’s official app lacks some basic functionality!

pinkfluffywolfie@lemmy.world on 08 May 21:32 collapse

Yeah, I use the molly fork because there’s features I like about it. I’d be sad if I couldn’t use it anymore. :(

EngineerGaming@feddit.nl on 09 May 09:47 collapse

What are the ones you’re after specifically?

pinkfluffywolfie@lemmy.world on 10 May 21:01 collapse

I’m not totally sure signal has it, but I like the ram shredding and socks proxy. I know molly isn’t fit for everyone’s threat model but those two features I do like to see so I use it instead; I’ve not run into any issues with it.

utopiah@lemmy.ml on 09 May 10:32 collapse

how do you know you’re interacting with an authentic signal client, and not a bastardized one.

I don’t think that’s the point… it does not matter. Even if it’s an authentic client, if the device (e.g. 0 day vulnerability on the OS) or the user (e.g. does not lock their phone while going to the bathroom) is compromised, your conversation is not secure.

throwawayacc0430@sh.itjust.works on 08 May 02:30 next collapse

I mean… you do know someone can just take a screenshot, right?

And even if you use the Android thing that blocks screenshots, they can still take a photo with another phone.

You need to trust the other person for there to be any “privacy”.

autonomoususer@lemmy.world on 08 May 04:37 next collapse

It’s their computing and their devices, not yours.

FauxLiving@lemmy.world on 08 May 05:59 next collapse

The direct answer to your question is: verification of the security of the platform that the other party is using is outside of the scope of the Signal protocol. Anything you send to the other party can be taken off of their device. Signal only concerns itself with securing the message over the network and making it hard for an adversary with network dominance to build a social graph. It doesn’t protect from all SIGINT.

Additionally, since the server is open source and the protocol is open an publicly documented, it is completely possible to build your own Signal client and give it whatever capabilities that you’d like.

There are several open source packages available that allow you to interface with Signal without using the official Signal client:

github.com/AsamK/signal-cli

gitlab.com/signald/signald (also, signald.org/articles/clients/ )

EngineerGaming@feddit.nl on 08 May 07:28 collapse

Those third-party clients have some essential, basic functionality that the official ones for some reason lack. Signal-cli allows registering from desktop without any smartphone, Molly allows an arbitrary Socks proxy instead of being limited to just Signal’s own proxy solution, tying a desktop client with a link instead of scanning a QR code (thus allowing easy registration from an Android VM), and maybe most importantly for some - Notifications not relying on Google (Molly-Socket allows it to use UnifiedPush).

irotsoma@lemmy.blahaj.zone on 08 May 06:04 next collapse

Signal isn’t that kind of app. It protects your data in flight, but only has minimal protections after the recipient gets the message. It’s a whole other game to protect data at the endpoint. If you can’t trust your recipients to protect data, then you shouldn’t send them data needing protection. In order to do that you need control over all levels of the device receiving the data, hardware, operating system, file system, and software. Anything else will always leave openings for data at rest at tge destination to be compromised by untrustworthy recipients.

SilliusMaximus@mander.xyz on 08 May 12:02 next collapse

Well yes, anyone can compile its own version of Signal and use it and it will work as long as there aren’t some major changes to its communication protocol

midtsveen@lemmy.wtf on 09 May 18:41 next collapse

This hole question slounda like a screenshot!

Screenahot? Yes! Stole data now? Yup!

Jason2357@lemmy.ca on 09 May 23:47 collapse

What is the threat model where this matters? You have to trust the recipient with Signal. The only one I can think of is the case where your recipient is using a compromised fork and is unaware. In this case, talking about the tool and checking with them about what they are using is really the only countermeasure.

root@lemmy.world on 10 May 06:54 collapse

Yeah, that’s a good point. For me it’s mostly family that is not very technical, so I’m not too concerned of them using a fork.