Information Security Stack Exchange is a question and answer site for information security professionals. It only takes a minute to sign up.
Sign up to join this community
I saw a video about the hacking of CCTV cameras:
He downloads the latest firmware from the internet.
He uses some reverse engineering on it.
He retrieves the password from etc/passwd file. And he logged in with root.
I don't understand why he downloads the latest firmware from the internet? As I understand it, the firmware is on the device, so we should do reverse engineering on that device.
The reason he downloaded it rather than getting it directly from the device is simply because it is easier to do it that way. When you download it, all you have to do is figure out the format and unpack it. When you take it from a device, you have to physically open up the device and often plug in complex logic probes and digital interfaces to the flash chip or EEPROM containing the firmware and extract it manually. That takes time and effort that could be alleviated simply by getting the firmware online.
There is the additional factor that you do not usually need to be in possession of the device in question to download its firmware. This can be important if the device is rare, expensive, or can only be purchased in another country. It sucks to have to open up and potentially damage a perfectly good device when you could just download the same firmware it uses and get the same results.
See also How do I extract a copy of an unknown firmware from a hardware device?
