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1110	5330	Challenge 3 Here's what we know.
5330	9350	With the update to the ADCS, the teams have regained control of the satellite.
9350	13350	But we still can't communicate with the payload module or operate the imager.
13390	17990	In addition, the majority of useful commands are not being accepted by the flight software.
17990	21510	We have to ask ourselves, what else did they damage on this satellite?
21610	25210	The challenge? Teams must restore communication with the payload module
25210	28930	so we can get it working again. Here's how they do it.
28930	32410	The teams find that their initial commands to communicate with the payload module are
32410	36930	not being accepted by the flight software. It's clear that the command and data handling
36930	42770	C&DH system is not working appropriately. In fact, payload commands, and the majority
42770	46830	of the other commands, have been disabled in the C&DH system.
47010	50750	It turns out the attacker has modified the C&DH flight software
50750	54470	and are now running their own code on board the space vehicle.
54570	58710	The attacker code is rejecting the majority of commands to the satellite including firmware
58710	65410	updates, firmware restore, and ADCS commands. As a result, it is not possible to restore
65410	68490	the failsafe image as the restore command has been disabled.
69210	73650	Lucky for the teams, the attacker was sloppy and inadvertently introduced a vulnerability
73650	79230	in the new firmware image. Teams exploit this vulnerability and use it to repair the system
79230	83390	and restore the C&DH software back to normal operation.
83450	87790	Once that is complete, they are able to communicate with the payload module once again.