Signal under fire for storing encryption keys in plaintext
Popular encrypted messaging app Signal is facing criticism over a security issue in its desktop application. Researchers and app users are raising
But.. That's how encryption keys are stored.
No your don't understand, you're supposed to encrypt the keys.
Then you encrypt that key
And then that key
Until it's all encrypted /s
opportunistic TPM integration would be nice.
I.e. use the security chip of the device, if one is found. Otherwise use password.
OR use a Nitrokey etc, which can act as a secure device to store these keys too.
Take that, Windows. You dont need a builtin TPM if you can use a Nitrokey 3 with a secure element, externally.
This same "discovery" gets reported on once or twice a year; it's starting to feel like a FUD campaign rather than actual research
Yeah but it really shouldn't be that way. Just add a pin or something, it's way too easy for people to just grab devices or install malware to leak keys. The current standard for security is that everything is encrypted at rest regardless of whole disk encryption.
Signal is still better that most of the stuff out there but it's not above well intentioned criticism
I just read the full article, and I'm not even that concerned about storing the key in plaintext. I find the possibility of copying the files, and then being able to run the same session simultaneously a lot scarier.
Not storing it in plaintext would require setting up some kind of password, right?
Some way to encrypt the decryption key.
This could also mean TPM + Pin. Or using a Nitrokey, externally, which stores the password to decrypt the decryption key.
That is how user account unlocking (on GrapheneOS with Pixel phones) is done.
Should the encryption keys be... encrypted?
With what? Where would you store the encryption key for the encryption key on a desktop system where it would not be accessible to an attacker?
Perhaps there could be a pin or password that must be entered every time to decrypt it into memory.
As the article states, currently all processes are able to read the file which contains the key. Instead, you could store the key in the macOS Keychain (and Linux/Windows equivalents), which AFAIK is a list of all sorts of sensitive data (think WiFi passwords etc.), encrypted with your user password. I believe the Keychain also only let's certain processes see certain entries, so the Signal Desktop App could see only its own encryption key, whereas for example iMessage would only see the iMessage encryption key.
Yo dawg
While true I don't get why this is long known and also news at the same time.
For Signal Backup tools for example this isn't a bug but a feature and the only way to make long term archival of chats possible.
You could archive chats encrypted too.
Yep, decrypt ... export elsewhere to csv txt json ... encrypt
If your computer is compromised to the point someone can read the key, read words 2-5 again.
This is FUD. Even if Signal encrypted the local data, at the point someone can run a process on your system, there's nothing to stop the attacker from adding a modified version of the Signal app, updating your path, shortcuts, etc to point to the malicious version, and waiting for you to supply the pin/password. They can siphon the data off then.
Anyone with actual need for concern should probably only be using their phone anyway, because it cuts your attack surface by half (more than half if you have multiple computers), and you can expect to be in possession/control of your phone at all times, vs a computer that is often left unattended.
"if you've lost physical security, you've lost all security."
I've heard criticism of the desktop app before as well, maybe they'll finally rework it?
Who is behind Stackdiary, btw?