LG Smart Refrigerator (LFX31995ST)
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This page will be dedicated to a general overview, descriptions, and information related to the LG Smart Refrigerator (LFX31995ST).
Pinouts
Exploitation
The LG Smart Refrigerator features two ways to gain privileges:
1: Connecting to the UART pinout above will drop you to a root shell when booted. From here, you can connect a USB flash drive to the device, and copy a secondary launcher to the system. Use the new one, from there you can launch a root shell utilizing the built in development tools.
2: Soldering the EMMC flash will allow you to copy a new launcher to the system partition. After rebooting the system the Android system will ask which launcher you wish to use. Use the new one, from there you can launch a root shell utilizing the built in development tools.
EMMC refers to an Embedded Multi-Media Card which has native Linux support. This means it works just like an SD card, and for our purposes, just filesystem access. Error Correcting Code and Out of Bounds data, which are usually a large hassle with NAND flash memory is handled in hardware, and is transparent, which makes it easier for reading and writing.
Although eMMC memory can have 9 Pins (VCC, VSS, CMD, CLK, DAT0-DAT4) it can also operate on SPI / Single Bit mode using only 1 DAT line. In short, reading/writing an eMMC chip can be done with only 5 wires, which does not require specialized hardware or software tools.
Required Minimum Connections: VCC, VSS, CMD, CLK, DAT0 (These lines all normally accessible via SMD resistors) Exploitee.rs recommends using a device like the SD Card Sniffer from Sparkfun to interface between your SD card reader, and the flash. By adding pins to the SD Card sniffer board, it facilitates easy analysis of the correct pinout, and also reduces the risk of damage due to repeated soldering to your SD card reader.
The LG Smart Refrigerator utilizes an EMMC flash. Using the pinouts above, you can connect the flash to a SD card reader, and rewrite it's contents.
For the LG Smart Refrigerator device specifically, you can mount the /system partition, which is EXT4. From here, copy a stock Android 2.3 launcher into system. The Refrigerator has a built in interactive shell, under debug settings. This will allow for root access via said shell and further examination of the system internals.