254
edits
Changes
Jump to navigation
Jump to search
Line 86:
Line 86: + + + + + + + + + + + + + + +
otp dumping is for chumps
! Public disclosure timeframe
! Public disclosure timeframe
! Discovered by
! Discovered by
|-
| Uncleared OTP hash keydata in console-unique 0x11 key-generation
| Kernel9Loader does not clear the [[SHA_Registers#SHA_HASH|SHA_HASH register]] after use. As a result, the data stored here as K9L hands over to Kernel9 is the hash of [[OTP_Registers|OTP data]] used to seed the [[FIRM#New_3DS_FIRM|console-unique NAND keystore decryption key]] set on keyslot 0x11.
Retrieving this keydata and the [[Flash_Filesystem#0x12C00|NAND keystore]] of the same device allows calculating the decrypted New3DS NAND keystore (non-unique, common to all New3DS units), which contains AES normal keys, also set on keyslot 0x11, which are then used to derive all current [[AES_Registers#Keyslots|New3DS-only AES keyXs]] including the newer batch introduced in [[9.6.0-24#arm9loader|9.6.0-X]]. From there, it is trivial to perform the same key derivation in order to initialize those keys on any system version, and even on Old3DS.
This can be performed by exploiting the "arm9loaderhax" vulnerability to obtain post-K9L code execution after an MCU reboot (the bootrom section-loading fail is not relevant here, this attack was performed without OTP data by brute-forcing keys), and using this to dump the SHA_HASH register. This attack works on any FIRM version shipping a vulnerable version of K9L, whereas OTP dumping required a boot of <[[3.0.0-6|3.0.0-X]].
This attack results in obtaining the entire (0x200-bytes) NAND keystore - it was confirmed at a later date that this keystore is encrypted with the same key (by comparing the decrypted data from multiple units), and therefore using another key in this store will not remedy the issue as all keys are known (i.e. later, unused keys decrypt to the same 0x200-bytes constant with the same OTP hash). Later keys could have been encrypted differently but this is not the case. As a result of this, it is not possible for Nintendo to use K9L again in its current format for its intended purpose, though this was not news from the moment people dumped a New3DS OTP.
| Derivation of all New3DS keys generated via the NAND keystore (0x1B "Secure4" etc.)
| None
| [[10.2.0-28|10.2.0-X]]
| ~April 2015, implemented in May 2015
| 13 January 2016
| [[User:WulfyStylez|WulfyStylez]], [[User:Dazzozo|Dazzozo]], [[User:Shinyquagsire23|shinyquagsire23]] (complimentary + implemented), [[User:Plutooo|plutoo]], Normmatt (discovered independently)
|-
|-
| enhanced-arm9loaderhax
| enhanced-arm9loaderhax