Debug was the third hardware hacking challenge of the Hack The Box Cyber Apocalypse Capture The Flag Competition. Hello world, welcome to Haxez, this challenge was a lot of fun and wasn’t too difficult provided you had the right extensions installed. The description for debug was as follows.
Your team has recovered a satellite dish that was used for transmitting the location of the relic, but it seems to be malfunctioning. There seems to be some interference affecting its connection to the satellite system, but there are no indications of what it could be. Perhaps the debugging interface could provide some insight, but they are unable to decode the serial signal captured during the device’s booting sequence. Can you help to decode the signal and find the source of the interference?
Debug With Logic 2
As with the first challenge, we needed to open the files with Logic 2. However, the answer wasn’t right in front of us like last time. I had previously used Logic 2 before during the Try Hack Me Advent Of Cyber. However, that challenge told us what analyzer we needed to use and the exact settings needed. I thought it would be best to start with Async Serial but I had no idea what the baud rate would be. There are ways to calculate the baud rate manually but thankfully there is also an extension.
Configuring The Analyzer
Once the extension was installed, I shift clicked from one high point of the signal to the other. This then provided an estimation of the baud rate. I added a new Aysnc Serial analyzer for the RX channel and gave it the correct baud rate.
Debug The Signal
Finally, the data window started producing text. I must admit that I thought this was cool. It reminded me of the film Aliens for some reason. Something to do with the ASCII art and the satellite dish I think. Anyway, a lot of text was spat out and I have to salute whoever made this because they didn’t need to put this level of detail into it. Hidden in this transmission was the flag and all you had to do was assemble it.
This was a really fun challenge but I have to be honest, I found it easier than the first challenge. With this challenge, I felt that I knew what I had to do immediately. The first challenge completely threw me off for a long time. I really appreciate the level of detail that went into the transmission. It made me smile. Anyway, that’s all for the hardware challenges. I couldn’t solve secret code and from the write-ups, I’ve read, it didn’t look easy.