I remember a time when visiting a website that opens a javacript dialog box asking for your name so the message “hi <name entered>” could be displayed was baulked at.
Why does signal want a phone number to register? Is there a better alternative?
I remember a time when visiting a website that opens a javacript dialog box asking for your name so the message “hi <name entered>” could be displayed was baulked at.
Why does signal want a phone number to register? Is there a better alternative?
I was unaware of this change, and it’s perfectly acceptable. No one has any ground to lambast Signal for requiring phone numbers to get an account. I think that’s a perfectly reasonable spam mitigation technique. The issue is having to shotgun your phone number to every Howard and Susan that you want to use Signal to communicate with.
This was honestly the only thing holding me back from actually using Signal. I’ll likely register for an account now.
If you are even remotely involved in any activist type of things, you certainly don’t want this US government honeypot have your phone-number and device id.
At least in theory, this is mitigated. The signal activation server sees your phone number, yes. If you use Signal, the threat model doesn’t protect you from someone with privileged network or server access learning that you use Signal (just like someone with privileged network access can learn you use tor, or a vpn, etc).
But the signal servers do not get to see the content of your group messages, nor the metadata about your groups and contacts. Sealed sender keeps that private: https://signal.org/blog/sealed-sender/
You would obviously want to join those groups with a user Id rather than your phone number, or a malicious member could out you. It’s not the best truly anonymous chat platform, but protection from your specific threat model is thought through.
edit: be sure to go to Settings > Privacy > Phone Number. By default anyone who already has your phone number can see you use signal (used for contact discovery, this makes sense to me for all typical uses of Signal), and in a separate setting, contacts and groups can see your phone number. You will absolutely want to un-check that one if you follow my suggestion above.
There are some mitigations in place, yes, but Sealed Sender on a centralized platform is snake-oil as someone with server access can easily do a timing attack and discover who communicated with whom.
That a timing attack could be successful is not a given. It’s a possibility, yes, but there is very likely sufficient mixing happening to make that unrealistic or unreliable. An individual doesn’t create much traffic, and thousands are using the server constantly. Calling it a honeypot or claiming the phone number and device is are available is a stretch.
Timing attacks can work in tor when you are lucky enough to own both the entrance and exit node for an individual because very few people will be using both, and web traffic from an individual is relatively heavy and constant to allow for correlation.
A timing attack is extremely realistic when you control one of the end devices which is a common scenario if a person gets arrested or their device compromised. This way you can then identify who the contacts are and with the phone number you can easily get the real name and movement patterns.
This is like the ideal setup for law inforcement, and it is well documented that honeypot “encrypted” messengers have been set up for similar purposes before. Signal was probably not explicitly set up for that, but the FBI for sure has an internal informant that could run those timing attacts.
Spam accounts are clearly the biggest factor for not letting anyone just sign up with an email. Although getting a new email without a phone verification is getting increasingly hard now.