Emoji

Author: noob-abhinav

Emojis everywhere! Is it a joke? Or something is hiding behind it.

you were given out.txt which contained a string of meaningless emojis. Putting them in a Unicode decoder gave the hex values and it was immediately obvious that only the last couple of bytes were changing.

some playing around with that last byte helped me figure out that the last byte was just an offset away from the ascii character, and the prefixed bytes were useless

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with open("./out.txt", "r") as FILE:
    for line in FILE.readlines():
        code = line.strip()
        if code[0:2] == '81':
            print(chr(int(code, 16) - 0x8140), end='')
        else:
            print(chr(int(code, 16) - 0x8080), end='')

where out.txt was the hex values of the encoded emojis. this gave finally

scriptCTF{3m0j1_3nc0d1ng_1s_w31rd_4nd_fun!1e46d}