Abusing the Internet of Things

I call it Encraption

Samsung allows users to download firmware that can be placed on a USB stick and connected
to its Smart TVs in order to perform upgrades. We will download the firmware for the
PN58B860Y2F model. In this case, we will analyze the firmware upgrade issued on Septem-
ber 22, 2009 (version 1013; see Figure 5-2).

FIGURE 5-2. Firmware upgrade downloads available on Samsung’s website

Even though the firmware upgrade file is in the Windows executable format of .exe, it is
also a ZIP file that can be uncompressed using the unzip tool:

$ unzip 2009_DTV_2G_firmware.exe

Archive: 2009_DTV_2G_firmware.exe

inflating: T-CHE7AUSC/crc

inflating: T-CHE7AUSC/ddcmp

creating: T-CHE7AUSC/image/

inflating: T-CHE7AUSC/image/appdata.img.enc

inflating: T-CHE7AUSC/image/exe.img.enc

extracting: T-CHE7AUSC/image/info.txt

inflating: T-CHE7AUSC/image/validinfo.txt

inflating: T-CHE7AUSC/image/version_info.txt

inflating: T-CHE7AUSC/MicomCtrl

inflating: T-CHE7AUSC/run.sh.enc

The important firmware image files appear to be T-CHE7AUSC/image/appdata.img.enc
and T-CHE7AUSC/image/exe.img.enc. Let’s see what happens when we inspect these files
using the strings tool, which is used to output the printable parts of binary files:

132 CHAPTER 5: THE IDIOT BOX—ATTACKING “SMART” TELEVISIONS