wicked-firmware [Unbreakable 2024]

14/04/24 rev

writeup by: zenbassi

Challenge Description

We need some info that is found inside this firmware.

Solution

We extract the filesystem of the firmware with binwalk. The flag is comprised of information such as the u-boot version, the extra entry in the hosts file and the admin line from the passwd file.

$ binwalk -e firmware.bin
DECIMAL   	HEXADECIMAL 	DESCRIPTION
--------------------------------------------------------------------------------
22372     	0x5764      	U-Boot version string, "U-Boot 1.1.4-g4df6eb16-dirty (Nov 30 2018 - 12:33:02)"
                                                    ^ this one
...

$ cd _firmware.bin.extracted/squashfs-root/

$ cat ./etc/hosts <- this one
...
127.0.1.1 842v3_un

$ cat ./etc/passwd
...
admin:x:1000:0:admin:/var:/bin/false <- this one
...