https://youtube.com/watch?v=Ai8J3FG8kys
If you have successfully extracted the root file system from the firmware file of your device, and if you want to understand what your device does after booting, and if there is an easy way to log in as root, this is the video for you!
We will talk about analyzing startup scripts of an IoT device to understand what the device does, if there is any possibility to login as root and to identify some interesting binary executables to reverse engineer to hack the device.
We assume that our device has a Linux or Unix like operating system, this is true for the overwhelming majority of devices; when some examples are needed we will analyze the startup scripts of our sample Gemtek Router (link below). We will start from the beginning that means from the boot of the operating system:
- we will look at what type of "init" process we have;
- we will analyze the init configuration file and related startup scripts;
- we will identify the most interesting binaries that manage our device;
- we will identify the login process;
- we will look if there is the possibility to access the device as root;
- we will use common Linux commands to do this analysis:
- a text editor;
- the "grep" command, to search inside a file or multiple files;
- the "find" command, to list files that interest us;
- the "xargs" command, often piped after the output of the "find" command and coupled to the "grep" command;
- the "strings" command, to display strings embedded in binary or executable files.
### Links with additional Information
Channel's Author: https://www.makemehack.com/2020/02/a-...
Channel's Web Site:
The sample router (Gemtek WVRTM-127ACN) on techinfodepot: http://en.techinfodepot.shoutwiki.com...
The sample router (Gemtek WVRTM-127ACN) reverse-engineered on GitHub, includes scripts to dump the EEPROM to a text file and to convert it back to binary file: https://github.com/digiampietro/hacki...
Hashcat, Advanced Password Recovery: https://hashcat.net/hashcat/
How to find and connect to the UART interface: https://youtu.be/6_Q663YkyXE
