I've been hearing for years people say "Signal requires phone number therefore I don't use it", and I've been hearing them mocked for years.
Turns out they were right.
Turns out they were right.
https://signal.org/blog/phone-number-privacy-usernames/
https://signal.org/blog/sealed-sender/
https://signal.org/blog/private-contact-discovery/
There isn't really anything you can do with that information. The first value is already accessible via other methods (since the phone companies carry those records and will comply with warrants). And for pretty much anyone with signal installed that second value is going to essentially always be the day the search occurred.
And like another user mentioned, the most recent of those warrants is from the day before they moved to username based identification so it is unclear whether the same amount of data is still extractable.
Ironically enough Reddit seems to have a pretty good take on this: https://www.reddit.com/r/law/comments/1qogc2g/comment/o21aeh...
I was genuinely surprised when I went to Reddit and saw that as the most voted comment on the story.
The lookups go through a secure enclave, the system is architected to limit the number of lookups that can be done, and the system has some fairly extensive anti-exfiltration cryptographic fuckery running inside the secure enclave to further limit the extent to which accounts can be efficiently looked up.
And of course you can also remove your phone number from contact discovery (but not from the acct entirely) but I'm not sure how that interacts with lookup for subpoenas. If they use the same system that contact discovery uses, it may be an undocumented way to exclude your account from subpoena responses.
The rest of what they say however is pretty spot on. The priority for signal is privacy, not anonymity. They try to optimise anonymity when they can but they do give up a little anonymity in exchange for anti-spam and user-friendliness.
So of course the ending notes of "use a VPN, configure the settings to maximise anonymity, and maybe even get a secondary phone number to use with it" are all perfectly reasonable suggestions.
And re: defaults the default behavior on signal is that your phone number is hidden from other users but it can be used to do contact discovery. Notably though you can turn contact discovery off (albeit few people do).
>We have also worked to ensure that keeping your phone number private from the people you speak with doesn’t necessitate giving more personal information to Signal. Your username is not stored in plaintext, meaning that Signal cannot easily see or produce the usernames of given accounts.
Extremely non trivial. What I'm hearing is "security by obfuscation".
I don't really think Signal tech has anything to do with this.
As a reminder... if you don't know all the people in your encrypted group chat, you could be talking to the man.
For users who configure Briar to connect exclusively over Tor using the normal startup (e.g., for internet-based syncing) and disable Bluetooth, there is no Bluetooth involvement at all, so your Bluetooth MAC address is not exposed.
Signal does give out phone numbers when the law man comes, because they have to, and because they designed their system around this identifier.
Signal can still tell law enforcement (1) whether a phone number is registered with Signal, and (2) when that phone number signed up and (3) when it was last active. That's all, and not very concerning to me. To prevent an enumeration attack (e.g. an attacker who adds every phone number to their system contacts), you can also disable discovery my phone number.
While Session prevents that, Session lacks forward secrecy. This is very serious- it's silly to compare Session to Signal when Session is flawed in its cryptography. (Details and further reading here https://soatok.blog/2025/01/14/dont-use-session-signal-fork/ ). Session has recently claimed they will be upgrading their cryptography in V2 to be up to Signal's standard (forward secrecy and post-quantum security), but until then, I don't think it's worth considering.
I agree that Briar is better, but unfortunately, it can't run on iPhones. I'm in the United States and that excludes 59% of the general population, and about 90% of my generation. It's not at fault of the Briar project, but it's a moot point when I can't use it to talk to people I know.
The question here is NOT "if Signal didn't leak your phone number could you still get screwed?" Of course you could, no one is disputing that.
The question is "if you did everything else perfect, but use Signal could the phone number be used to screw you?" The answer is ALSO of course, but the reason why we're talking about it is that this point was made to the creator of Signal many many times over the years, and he dismissed it and his fanboys ridiculed it.
I assume because of the baseband stuff to be FCC compliant? Last I checked that meant DMA channels, etc. to access the real phone processor. All easily activated over the air.
Indeed. The only reason this is not used by customer support for more casual access, firmware upgrades and debugging is a matter of policy and the risk of mass bricking phones and as such this is not exposed to them. There are other access avenues as well including JTAG debugging over USB and Bluetooth.
FCC devices are certified / allowed to use a spectrum, but you must maintain compliance. If you're a mobile phone manufacturer you have to be certain that if a bug occurs, the devices don't start becoming wifi jammers or anything like that.
This means you need to be able to push firmware updates over the air (OTA). These must be signed to avoid just anyone to push out such an OTA.
The government has a history of compelling companies to push out signed updates.
If there's one thing we learned from Snowden is that the NSA can't break PGP, so these people who live in the world of theory have no credibility with me.
I never saw a single speck of anything I ever sent to anyone via PGP in there. They had access to my SIGAINT e-mail and my BitMessage unlocked, but I used PGP for everything on top of that.
Stay safe!
And even then, a trusted participant could not understand they're not supposed to give their private keys out or could be rubber-hosed into revealing their key pin. All sorts of ways to subvert "secure" messaging besides breaking the crypto.
I guess what I'm saying is "Strong cryptography is required, but not sufficient to ensure secure messaging."
SimpleX does better than Session because the address used to add new contacts is different from the address used with any existing contact and is independently revocable. But if that address is out there, you can receive a full queue of spam contacts before you next open the SimpleX app.
Both Session and SimpleX are trivially vulnerable to storage DoS as well.