Part 2/4:
The process begins by identifying the key components of the router – the main CPU and the SPI (Serial Peripheral Interface) flash chip. The SPI flash chip contains the firmware that runs on the CPU, and by extracting this firmware, we can analyze the code and identify potential security issues.
The CH341A allows us to read the SPI flash chip without the need for desoldering, a process that can be risky and potentially damage the device. By clipping the CH341A onto the exposed pins of the SPI flash chip, we can use a program like Flashrom to communicate with the chip and extract the firmware.
Once the firmware is extracted, we can use tools like Binwalk to dissect the file, uncovering hidden gems such as the U-Boot bootloader and the root file system. This gives us access to the actual code running on the router, enabling us to dive deep into the software and search for vulnerabilities.
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