HACKvent 2020 - Day 15

01-01-2021 - 3 minutes, 21 seconds - CTF

Challenge - Man Commands, Server Lost

Elf4711 has written a cool front end for the linux man pages. Soon after publishing he got pwned. In the meantime he found out the reason and improved his code. So now he is sure it’s unpwnable.

Notes

  • You need to start the web application from the RESOU...

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HACKvent 2020 - Day 14

01-01-2021 - 4 minutes, 36 seconds - CTF Reverse Engineering

Challenge - Santa's Special GIFt

Today, you got a strange GIFt from Santa:

Image of a small pixelated metal file

You are unsure what it is for. You do happen to have some wood lying around, but the tool seems to be made for metal. You notice how it has a rather strange size. You could use it for your fingernails, perhaps? If you k...

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HACKvent 2020 – Day 13

01-01-2021 - 2 minutes, 31 seconds - CTF

Challenge - Twelve steps of christmas

On the ninth day of Christmas my true love sent to me...

nineties style xls,
eighties style compression,
seventies style crypto,
and the rest has been said previously.

5862be5b-7fa7-4ef4-b792-fa63b1e385b7.xls

Hints: Wait, Bread is on the Nice list? B...

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HACKvent 2020 - Day 12

01-01-2021 - 3 minutes, 35 seconds - CTF

Challenge - Wiener waltz

During their yearly season opening party our super-smart elves developed an improved usage of the well known RSA crypto algorithm. Under the “Green IT” initiative they decided to save computing horsepower (or rather reindeer power?) on their side. To achieve this they chos...

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HACKvent 2020 - Day 11

01-01-2021 - 2 minutes, 22 seconds - CTF

Challenge - Chris'mas carol

Since yesterday’s challenge seems to have been a bit on the hard side, we’re adding a small musical innuendo to relax.

My friend Chris from Florida sent me this score. Enjoy! Is this what you call postmodern?

Image of a music sheet

Hints: He also sent this image, but that doesn’t loo...

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HACKvent 2020 - Day 10

01-01-2021 - 2 minutes, 56 seconds - CTF

Challenge - Be patient with the adjacent

Ever wondered how Santa delivers presents, and knows which groups of friends should be provided with the best gifts? It should be as great or as large as possible! Well, here is one way.

Hmm, I cannot seem to read the file either, maybe the internet knows...

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HACKvent 2020 - Day 9

01-01-2021 - 1 minute, 21 seconds - CTF

Challenge - Santa's Gingerbread Factory

Here you can customize your absolutely fat-free gingerbread man.

Note: Start your personal instance from the RESOURCES section on top.

Goal / Mission: Besides the gingerbread men, there are other goodies there. Let’s...

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HACKvent 2020 - Day 8

01-01-2021 - 3 minutes, 2 seconds - CTF

Challenge - The game

Let's play another little game this year. Once again, as every year, I promise it is hardly obfuscated.

Solution

The file contained an obfuscated Perl script, neatly formatted to look like tetris. Of couse, when ran, it really...

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HACKvent 2020 - Day 7

01-01-2021 - 6 minutes, 27 seconds - CTF

Challenge - Bad morals

One of the elves recently took a programming 101 course. Trying to be helpful, he implemented a program for Santa to generate all the flags for him for this year's HACKvent 2020. The problem is, he can't remember how to use the program any more and the link to the documentat...

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HACKvent 2020 - Day 6

01-01-2021 - 2 minutes, 31 seconds - CTF

Challenge - Twelve steps of christmas

On the sixth day of Christmas my true love sent to me...

six valid QRs,
five potential scrambles,
four orientation bottom and right,
and the rest has been said previously.

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