Notice from qwjiibow:
Challenge completed by.... drum role....
mastercomputers
Hi guys, ive noticed that these web based hacking challenges are quite popular.
so ive decided to release one.
Its not web based, it doesnt require much prior knoledge, but should be quite hard.
actually, no, it seems hard, but in fact is very easy, depending on how many clues i give away.
infact, for those of you who really think hard about this, it bmay be too easy.. i dont know.
here is the challenge:
I have encrypted a random html webpage that i have downloaded from a random web-site.
it is your job to de-crypt it.
the encrypted page is quite large, believe me, the larger the page, the more patterns will emerge and the easyer this challenge should be.
here is how the encryption works, it uses Xor logic.
0 xor 0 = 0
0 xor 1 = 1
1 xor 0 = 1
1 xor 1 = 0
10100110 << data byte
01010011 << password byte
11110101 << encrypted byte
google for Xor encryption for more information.
This type of encryption was first used over 400 years ago by japanese warriors, and was broken almost 100 years ago by a mathematician with no computers, and the message was plain english, much harder to de-crypt than the structured html code.
when you have broken the encryption, PM me, and i will add you to the wall of fanme.
RULES:
any software you use to brute force the password MUST be written by yourself. please include source code in the PM you send.
Ive seen this type of encryption broken with just a graph of the occurances of each byte, so programming knoledge is not needed, but will be usefull.
HINTS:
all '<' characers are normally very quickly follwed by '>'
tags such as <html> will be expected very neer the top of the html file.
think of other pattern with html, andcharacters that should show up often.
maybe the last 6 characters will be </html> which would give at least 7 password characters
(no, i made such this tag qwas not at the very end... but it is very close) (plus, the password is quite weak, ive not dicided on it yet, but it will porbably be quite weak, less than 7 characters, who knows [ me] )
if you look hard enough, you will find patters of characters.
the size of the patterns, and spacing between them will give valuable clues as to the size of the password.
the file was taken from a Unix server,
for those who dont know, in Unix, a newline is a \n character (ascii code 10)
in windows, a newline is both a \n and a \r
so when you have sucessfully de-crypted the file, viewing it in notepad will probably show the document without new-lines... dont worry, its just widnows beeing annoying.
the source code of the porgram i used to encrypt the web page is added to this post as an attachment.
you dont need it, but it may give a better understanding of how it works.
this is vry weak encryption.
when compiled as the porgram xor.exe
useage:
xor input_file output_file password.
because xor works both ways forwarsda and backwards,
running xor on a plain file wil encrypt it.
running xor on an encrypted file will de-crypt it.
the encryped file you need to de-crypt is added as an attachment to this post...
as time goes on if noone gets it, maybe ill post some clues...
or maybe i will assume that this hackers challenge is too hard, and late it fade into oblivion..
or maybe i made it too easy, lol.
(this IS easy, it just looks very hard, especially when you first look at the encrypted file with notepad.)
