2016 RC3 CTF writeup -- Cats (Crypto 300)
We first get a gif by downloading the file attached.
The cats are cute and annoying....
The description had said that we only need to figure out the last 8 alphabets of the flag.
By using online tools to extract the frames of the gif, we got 8 pictures from the gif.
As we can see, there are different numbers of cats in each frame. There are 14, 9, 1, 20, 23, 15, 5, 13 separately in the frames. The trick here is that the cat tail in the first frame is not counted as a cat. We transform the number into alphabets by alphabets order and got "NIATWOEM". Reverse the string and we get "MEOWTAIN" which seems to be a more meaningful phrase.
flag: RC3-2016-MEOWTAIN
Don't know why it worths 300 points.
The cats are cute and annoying....
The description had said that we only need to figure out the last 8 alphabets of the flag.
By using online tools to extract the frames of the gif, we got 8 pictures from the gif.
As we can see, there are different numbers of cats in each frame. There are 14, 9, 1, 20, 23, 15, 5, 13 separately in the frames. The trick here is that the cat tail in the first frame is not counted as a cat. We transform the number into alphabets by alphabets order and got "NIATWOEM". Reverse the string and we get "MEOWTAIN" which seems to be a more meaningful phrase.
flag: RC3-2016-MEOWTAIN
Don't know why it worths 300 points.
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