low-end device with unofficial grapheneOS

grayway2

https://www.punkt.ch/products/mc03-premium-secure-smartphone

https://www.gsmchoice.com/en/catalogue/punkt/mc03/

MediaTek Dimensity 7300
(6-digit pin BFU bypass within seconds)

Only 745€ !

keycap_puller

Nowhere near GOS. I don't see any real GOS features. It's just an AOSP fork slapped together with a bunch of third-party software and gimmicks.

schweizer

745€ for a low end smartphone is by no way cheap, it's overly expensive.

Novaliss

https://discuss.grapheneos.org/d/18216-apostrophy-mobile-system-punkt-mc02

Novaliss

grayway2 Only 745€ !

Not only that, you also get 50% off bying their 76€ t-shirt!

Kamika242

Novaliss their 76€ t-shirt!

Typical swiss prices ... ^^

de0u

grayway2 Why is "unofficial grapheneOS" in the thread title? Does Punkt claim they are shipping GrapheneOS?

Pocketstar

schweizer Indeed, I see in my country, a brand new unlocked Pixel 128GB 10a is €450 (no subscriptions)
https://www.belsimpel.nl/google-pixel-10a/128gb-zwart
(I am not affiliated to this store, I just like them personally, very reliable)

Novaliss

de0u Does Punkt claim they are shipping GrapheneOS?

From reading trough their pages, it seems like they don't anymore.

userofgos

https://xcancel.com/GrapheneOS/search?f=tweets&q=Punkt&since=&until=&min_faves=

Punkt previously marketed devices they claimed ran GrapheneOS which weren't in reality. They didn't provide bare minimum updates and well increasingly far behind. Since they weren't providing basic updates, their port of sandboxed Google Play fell apart and didn't work properly.

Punkt has no devices running GrapheneOS. They have a fork of Android 13 with some LineageOS and GrapheneOS changes. GrapheneOS is solely based on Android 16. Using portions of our code doesn't make something a GrapheneOS device.

grayway2

de0u They used but not anymore. They still use some grapheneOS code. They claim to sell a secure smartphone but the mc03 is based on Android 15 with a MediaTek chipset. A forensic examiner can extract a physical image of the device which is normally only possible with root access. Hardware keys are also extracted so it's trivial to brute-force the user PIN.

The most saddest part to me is that people will buy it and really think that they're using a real secure and private phone while in reality Punkt is literally fucking the customer with false claims and overpriced phone.

schweizer

To make false claims is a fraud and fraud is an offence requiring public prosecution in Switzerland. Anyone, even living abroad can file a complaint. It is for free unless you make false accusations (which I strongly discourage). You do not have to buy a phone first. IANAL.

AleniaGoldBerg

grayway2 Android based devices are unlocked via the hardware but also the user's password. Even if the hardware was compromised the Police wouldn't get in without also getting the user's password.

de0u

AleniaGoldBerg Even if the hardware was compromised the Police wouldn't get in without also getting the user's password.

Many users rely on hardware throttling to block brute-force attempts and use a fairly short PIN or passphrase. That's why grayway2 mentioned brute-forcing along with the hardware bypass. Using a long and genuinely-random passphrase can work, but it is prohibitively inconvenient for most users.

DeletedUser928

@AleniaGoldBerg: Police wouldn't get in without also getting the user's password

<TinFoilHatOn> Ha, you are assuming that the whole TPM/Titan M is not already double keyed :) . Go ahead, prove that it is not. I'll wait...</TinFoilHatOn>

AleniaGoldBerg

DeletedUser928 I don't know what double keyed means. I would like for you to elaborate on that though.

DeletedUser928

AleniaGoldBerg

So the Trusted Platform Module (Titan M/Tensor chip in the case of the modern Pixel phones) is sort of a standalone computer/vault, whose sole purpose is to store credentials and deal with authentication while running in parallel to the Android system. TPM internals are, more-less, a closely guarded secret (for all manufacturers) and peer review is practically non-existent. Forget about FOSS code. Verification is usually limited to "trust us, bro" .

The TPM stores credentials (like disk encryption keys(LUKSetc), password, passkeys, etc) by encrypting them with keys derived from your password/pin/fingerprint etc.

If Google wanted to (or was mandated by some 3 letter agencies), they could create a TPM that would also maintain a second copy of your enrolled credentials, but these would be encrypted using some key that is only know to Google (or others involved).

This way, anyone who had access to this "second" key (google, govt, etc), could simply decrypt the second copy of the credential database without having to crack your keys.

<TinFoilHatOn>No way to convince me this is not done already.</TinFoilHatOn>

AleniaGoldBerg

DeletedUser928 Well I'm about to convince you this hasn't already been done. You see on GrapheneOS or even normal Android even if the Secure Element is compromised the password is still required for key derivation. All the secure element does is essentially just mostly rate limiting. This is why LUKs on Linux is still secure even without a TPM because key derivation doesn't need secure hardware. It's kind of hard to explain because all the math into it but essentially your password itself is encrypting the master key.

DeletedUser928

AleniaGoldBerg

You missed the point.

How do you know there is not a second key, used in parallel to your derived keys, also encrypting the master key and duplicate things in the Hardware Security Module (I have been incorrectly calling it TPM because of habbit, but HSM is more correct)? All of that gets done by the chip. For LUKS, it is easy to prove as long as you stick to FOSS+no TPM/HSM. For Titan M(2) etc, while its design is technically "open", how do you know what is actually baked into the chip?

P.S. The math part used to not scare me at all (in fact, that is what made me comfortable with PKC). Some 20 years ago, or so, I was still able to do RSA and DH by hand on paper (with a simple calculator, of course). No more coprimes or crt for me these days, though!

de0u

DeletedUser928 <TinFoilHatOn> Ha, you are assuming that the whole TPM/Titan M is not already double keyed :) . Go ahead, prove that it is not. I'll wait...</TinFoilHatOn>

It is very hard to prove that any conspiracy theory is false! For example, can you prove that your post isn't part of a conspiracy to cause people to distrust what might be the most secure generally-available platform, so more people pick easily-compromised phones?

With respect to the Titan M2 in particular...

People do analyze the Titan chips "from the outside" (example).
Keeping a deliberate back door in the Titan chips secret would require a lot of people to participate in the conspiracy for a long time without whistleblowing

So, there may be no "proof", but there are many true things that aren't provable.