3 ms·

It's only a matter of time until a company starts selling TPM dumps, right?

blibble 3y ago
maybe, but for a task like this it doesn't really scale Apple aren't going to allow one phone to attest 5000 new iMessage clients
- kotaKat 3y ago
  That's... amusingly, also a thing in Chinese marketplaces, for a similar purpose. iCloud Activation Lock, on non-cellular devices (eg, Wi-Fi only iPads), relies on the device's serial number, Wi-Fi MAC, and Bluetooth MAC addresses as the three identifiers required to clear the Activation Lock check. Via special debug cables (eg, a "DCSD cable") there are ways to write in new SysCfg data to the flash to change those variables. This can also be done to Apple Watches (pre-Series 6) with a special dock also sold on the Chinese market. You can (sort of easily) get your hands on a "clean" serial/MACs set for under $10-15 or so on the market.
  - Eriksrocks 3y ago
    Interesting. I assume this is mostly used to "wash" stolen devices to make them appear legitimate for resale? I'm surprised Apple designed the hardware to allow this without any sort of authentication.
Eriksrocks 3y ago
You can't "dump" a TPM. That's the whole point. They are designed such that the cryptographic secrets they hold (including ones loaded at manufacturing) are unrecoverable without an electron microscope and nation-state level resources (and even then, it would be extremely difficult if not impossible on modern process nodes).
- SpaghettiCthulu 3y ago
  > You can't "dump" a TPM. > unrecoverable without an electron microscope and nation-state level resources (and even then, it would be extremely difficult if not impossible on modern process nodes). Oh, so you can. It's only a matter of time.
- loopdoend 3y ago
  Even with an electron microscope you wouldn't extract a root key it would just be a device key which they would then ban.
  - SpaghettiCthulu 3y ago
    There's plenty that one would be able to do with a device key before it is banned.

maybe, but for a task like this it doesn't really scale Apple aren't going to allow one phone to attest 5000 new iMessage clients

kotaKat 3y ago
That's... amusingly, also a thing in Chinese marketplaces, for a similar purpose. iCloud Activation Lock, on non-cellular devices (eg, Wi-Fi only iPads), relies on the device's serial number, Wi-Fi MAC, and Bluetooth MAC addresses as the three identifiers required to clear the Activation Lock check. Via special debug cables (eg, a "DCSD cable") there are ways to write in new SysCfg data to the flash to change those variables. This can also be done to Apple Watches (pre-Series 6) with a special dock also sold on the Chinese market. You can (sort of easily) get your hands on a "clean" serial/MACs set for under $10-15 or so on the market.
- Eriksrocks 3y ago
  Interesting. I assume this is mostly used to "wash" stolen devices to make them appear legitimate for resale? I'm surprised Apple designed the hardware to allow this without any sort of authentication.

Eriksrocks 3y ago

You can't "dump" a TPM. That's the whole point. They are designed such that the cryptographic secrets they hold (including ones loaded at manufacturing) are unrecoverable without an electron microscope and nation-state level resources (and even then, it would be extremely difficult if not impossible on modern process nodes).

SpaghettiCthulu 3y ago
> You can't "dump" a TPM. > unrecoverable without an electron microscope and nation-state level resources (and even then, it would be extremely difficult if not impossible on modern process nodes). Oh, so you can. It's only a matter of time.
loopdoend 3y ago
Even with an electron microscope you wouldn't extract a root key it would just be a device key which they would then ban.
- SpaghettiCthulu 3y ago
  There's plenty that one would be able to do with a device key before it is banned.