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xyberz09 · Newbie Joined: Nov 21, 2009 Posts: 11 Points: 565

I'm stuck with this one and have no idea what kind of encryption this is, so I Googled a bit for 'christmas cipher' (pretty lame, I know) and found this:

> http://www.jdueck.net/article/17/a-cipher-for-christmas

This looks quite a bit like the cipher used for the chall, but unfortunately no one has solved it yet Sad

Some hints I got from the page:

1. It's a simple substitution cipher
2. It's got a few 'cruel' twists

(got the above hints from Google)

TrueHacker · Posted: Thu Nov 26, 2009 9:18 am Post subject:

I like the thinking with looking for a christmas cipher, but I went another way with this. It uses a fairly common cipher and incorporates a number, maybe a number having to do with Christmas Smile

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xyberz09 · Newbie Joined: Nov 21, 2009 Posts: 11 Points: 565

Thanks for the hint. I'll try solving it now Smile

Since the cipher uses a number (realted to Christmas), this has to be a cipher with a key, right? So, it can't be solved unless I have a valid key?

Off to look for ciphers (simple ones) that need a key Very Happy

xyberz09 · Newbie Joined: Nov 21, 2009 Posts: 11 Points: 565

Hmmmm... I searched the web (Wikipedia, Google, Braingle, Rumkin, etc.) for the kind of encryption cipher that generates ciphertext that looks like the ciphertext provided in the challenge, but I haven't had any success... yet.

Could you provide me with some hint as to what kind of cipher this is?

vbms · Newbie Joined: Oct 06, 2009 Posts: 9 Points: 1070

so i found a tool that is producing similar output with numbers as key but other tools that have that cipher are producing different output?? ok i think it cant be that cipher ... hmmm

MAW · Newbie Joined: Dec 17, 2009 Posts: 22 Points: 685

I think the clue is in how the data is presented rather than the whole 'Christmas' thing, it can be broken just as easily without being told the clue Christmas.

I saw one like this on another Wargame recently, I spotted it straight away. I beat it first time by turning the ciphertext into Denary and comparing the numbers. Think number ranges, the alphabet and layer-6.

Does that help anyone?
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