Test your cracking skills :)

iceman · Post by **iceman** » Wed May 19, 2004 12:28 am

ive made a little encrypted bmp file (crypted.bmp) for you to crack and have also included the decryption program (decrypt.exe) !

if you view the file it shows as random color dots
run the decrypter and enter the code it will generate a new file called decrypt.bmp

get the code right and you will see the hidden picture and message, get the code wrong and you just get more random pixels

have fun

k · Post by k » Wed May 19, 2004 1:09 am

Any requirements to run it? I get a Runtime error on XP Pro. I'm running it from C:\Documents and Settings\k\Desktop\New Folder if that makes a difference.

Enter decryption code : iceman
Runtime error 106 at 0000:01E7!

k · Post by k » Wed May 19, 2004 1:16 am

Found the problem. No input validation

You didn't specify that the "code" had to be 0 - 9. And it looks like there is some maximum length to the code since I get a runtime error if I enter a lot of digits (buffer overflow?).

Do you work for Microsoft?

Just giving you a hard time. LOL

I'll see if I can figure it out.

Edit: Looks like 10 digits is the maximum length?
Edit: Nope, since 0123456789 works and 6757747369 doesn't. *scratches head*
Edit: Looks like the code is being converted to a 32-bit signed integer. So the range of values will be from -2147483648 through 2147483647.

This might take a while.

iceman · Post by **iceman** » Wed May 19, 2004 3:57 am

glad too see you have taken on the challenge

GOOD LUCK

looks like there is some maximum length to the code since I get a runtime error if I enter a lot of digits (buffer overflow?). Do you work for Microsoft?

hehe

Found the problem. No input validation

well i didnt want to make it too easy lol
all im gonna say is that the number is positive decimal integer

{ i was originally gonna make the code input ascii and hash the bits into a number but was feeling too lazy lmao }

Marrow · Post by **Marrow** » Wed May 19, 2004 4:47 am

before i begin, is it cheating if i use a disassembler?

iceman · Post by **iceman** » Wed May 19, 2004 12:22 pm

before i begin, is it cheating if i use a disassembler?

funny

i thought thats what cracking was all about

you'll see how it works once you disassemble it although i dont think it will help

if nobody manages to crack it i'll post the correct code here

nicolas.b · Post by **nicolas.b** » Wed May 19, 2004 1:44 pm

this is a challenge i'm probably going to pass on at the moment, but i just wanted to say i really enjoy the way the veins in your head throb to the beat and how that one mole on your forehead keeps doing such a funky fresh dance...

iceman · Post by **iceman** » Wed May 19, 2004 2:28 pm

nicolas.b wrote:this is a challenge i'm probably going to pass on at the moment, but i just wanted to say i really enjoy the way the veins in your head throb to the beat and how that one mole on your forehead keeps doing such a funky fresh dance...

ooookaaay

Post by **Tank Program** » Wed May 19, 2004 4:20 pm

I'll take the challenge. Better set it up to brute force before I start trying to finnesse it. First step, check and see if I have enough hard drive space for 4 billion or so 30KB files... So does anyone have 120000GB free? Let me check my math again... Oh wait, that's right... Time to come up with new plan...

iceman · Post by **iceman** » Wed May 19, 2004 5:34 pm

i typed a long post of tips on how you could easy brute force this without needing all the storage but just before i clicked submit i decided to let it run a little longer so i clicked back instead

i'll wait till you guys give up lol

Post by **Tank Program** » Wed May 19, 2004 5:38 pm

I've found some good resources on cracking, and I have the next four days off from school

. I think I'll get it...

iceman · Post by **iceman** » Wed May 19, 2004 5:43 pm

i hope you do

cant wait to see the decrypted picture posted here

Post by **Tank Program** » Wed May 19, 2004 5:46 pm

Then again, I am awfully tempted to spend some time playing games right now... I'll come back to it...

k · Post by k » Wed May 19, 2004 6:46 pm

*tries a little social hacking*

*phone rings*
Hey ice, this is k, your sys admin. There seems to be a problem with your encryption program. It seems to be generating garbage for output. I need to know your code so I can make sure it is working correctly and possibly fix the problem. Thanks.

iceman · Post by **iceman** » Wed May 19, 2004 6:58 pm

nice try

but i know my evil code is fully working