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+++
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author = "Maik de Kruif"
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title = "Challenge 0 - AdventOfCTF"
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date = 2020-12-02T17:20:28+01:00
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description = "Challenge 0 of AdventOfCTF."
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tags = [
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"AdventOfCTF",
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"challenge",
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"ctf",
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"hacking",
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"writeup",
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]
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categories = [
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"ctf",
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"writeups",
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"hacking",
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]
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+++
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- Points: 1
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## Description
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Do you remember the flag in the teaser website?
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## Solution
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Use the Wayback Machine to get the teaser page.
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<https://web.archive.org/web/20201112020839/https://adventofctf.com/>
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When taking a look at the source we find the following comment:
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```html
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<!-- Ceasar worked on this you know. Tk9WSXtIRVlfMVNfVGgxU19AX0ZsYTk/fQ== -->
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```
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If we then use `base64` to decode this string we get `NOVI{HEY_1S_Th1S_@_Fla9?}`.
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```bash
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> echo "Tk9WSXtIRVlfMVNfVGgxU19AX0ZsYTk/fQ==" | base64 -d
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NOVI{HEY_1S_Th1S_@_Fla9?}
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```
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This flag can then be submitted for the [challenge](https://ctfd.adventofctf.com/challenges#0-1).
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