Drone Wars 1
State of the art
We have 2 files: Capture.zip
and capture.wav
. There is a binary file in the zip archive, don’t worry about it for now.
After several hours of crawling the internet searching for datas about the .wav files, I found a stego technic: SSTV.
I found a tool for linux: qsstv
.
Decoding the .wav
I run QSSTV
with VLC
in background, set my audio output into QSSTV, and:
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ECW{da553166e44a3151dfe422c34f693fe6}
Drone Wars Hint 1
Like the first Drone Wars challenge, we have a horrible .wav
file. Let’s try with QSSTV:
Same thing :)
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ECW{SHELLCODES}
Drone wars 2
In the first challenge, we got a QR code. It contained the following data:
6xVeMcAx2zHJs0WwKjEEDkE5y3X4/+bo5v///xvqG/Eb4xv4mi6ZK8Emc5gAPueqG+pqG/HnqsLF1dXVbwBpfVFLHhtPT05LGxNOThlJABlMThJITxIbGEgdEkxMHBsASE9IVyA=
Decoded:
\xeb\x15^1\xc01\xdb1\xc9\xb3E\xb0*1\x04\x0eA9\xcbu\xf8\xff\xe6\xe8\xe6\xff\xff\xff\x1b\xea\x1b\xf1\x1b\xe3\x1b\xf8\x9a.\x99+\xc1&s\x98\x00>\xe7\xaa\x1b\xeaj\x1b\xf1\xe7\xaa\xc2\xc5\xd5\xd5\xd5o\x00i}QK\x1e\x1bOONK\x1b\x13NN\x19I\x00\x19LN\x12HO\x12\x1b\x18H\x1d\x12LL\x1c\x1b\x00HOHW
Wow, cool, bullshit. Let’s try with le old bruteforce technique. Rotation? Nope. XOR ? Yes! It was a one byte key.
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�?to��_��������1�1�1�1Ұ�� Y�̀1�@1�̀�����ECW{a41eeda19dd3c3fd8be812b78ff61beb}
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ECW{a41eeda19dd3c3fd8be812b78ff61beb}
Drone wars hint 2
State of the art
We have a JPG picture, a lot of steg stuff can be effective.
Guessing of the year
I went with the steghide
tool… And the steghide passphrase: ECW
.
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Morse to binary
Input:
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Output and flag:
FILE SOURCE - GFSK DEMOD - PACKET DECODER - FILE SINK
Drone wars 3
State of the art
Do you remember the binary file in the zip archive in the Drone Wars 1 challenge? The Capture.bin
one. Thanks to the Drone Wars 2 hint, we now know that we have to use GNU Radio
.
File source, GFSK demode, etc… Are GNU Radio blocks to decode a source file.
GNU Radio
I choose this configuration:
- File source -> GFSK Demod: Complex mode
- GFSK Demod -> Packet decoder -> File Sink: Byte mode
Let’s run this, and see what kind of data there is in our toto.bin
file:
GPS to ASCII
By googling gps to ascii
, I found this website:
I format my toto.bin
into a valid CSV file for this website:
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And then (when zooming):