XyliBox: crackme

Saturday, 21 January 2012

QuickBasic CrackMe

I got QuickBasic recently, and the idea to make a crackme, a simple thing:

But i've absolutely no idea about how to unpack/crack this 20 year old stuff.
if you guys want try, you can find a compiled version here http://pcloud.crdf.net/xylitolpublic/crackme_qbasic.zip
Work on windows XP, not sure for vista/7

Edit 22 Jan 2012: Gotcha!1

Wednesday, 9 March 2011

Hyperlisk Brainfuck crackme #1

I succesfully recovered all of my files from a broken hard drive, and found a old 2008 crackme done by a friend (where are you now ?).

But it's not a usual crackme... a brainf*ck one.

In case you didn't know, Brainfuck is one of those turing complete languages that has no apparent use in the real world.

But hey, being very very simple with a limited grammar, writing an interpreter should be easy.

I've already see a BF interpreter written entirely in standard LOLCode

crackme.bf ~

>++++++++[->++++++++<]>++.++++.<++++++[->------<]>--.<+++++++[->+++++<]>.<++++++
+[->++++++<]>+++++.<++++[->----<]>-.++.++++++++.<++++++[->-----<]>.<++++++[->+
+++<]>.<++++++++[->--------<]>-----.+++.++++++++++++++.<++++++[->------<]>---.<+
+++++++[->+++++++<]>+.<+++++++[->++++++<]>+++++.-------------.----.<++++[->+++
+<]>+++.<+++++[->---<]>.-.<++++++++[->--------<]>----.<++++++[->+++++<]>++++.<++
+++++[->+++++++<]>++++++.<+++++++++[->-------<]>.<+++++[->-----<]>-.<++++++[->++
++++<]>++++.<+++++++[->+++++++<]>.---------.-----------.+++++++++++++.------.---
.++++++++++.--------.<++++++++++[->---------<]>-------..<+++++++++[->++++++++<]>
+++++.<++++[->++++<]>+.-------.<++++[->++++<]>+++.<+++++++++[->---------<]>---.<
+++++++++[->++++++++<]>+.++++++++++.<+++++++++[->---------<]>--.<+++++++++[->+++
++++++<]>+++.------------.---.<++++++++[->--------<]>-----.<++++++++++[->+++++++
+<]>.<+++++[->---<]>.<++++[->++++<]>++..++++.--------.+++.--------------.<++++++
[->------<]>-.<+++++++[->-------<]>----.[<]>[-]>[-]>>>>>>>>>>>+<<<<<<<<<<<++++++
+++[-<++++++++>]>[-]+++++++++++[-<+++++++++++>]>[-]+++++++++++[-<++++++++++>
]<++>>[-]++++++++++[-<++++++++++>]<+>>[-]+++++++++++[-<++++++++++>]<++++>>[-],--
--------[++++++++++>,----------]<<[<]>[[-<<<<<<->>>>>>]<<<<<<[+[>]>-<]>+[-<]<[<]
>>>>>>>>]>-[[-]>[-]<+++++++++[->+++++++++<]>++.<+++++[->+++++<]>+++.+++..+++++++
.<+++++++++[->--------<]>-----.------------.<+++++++++[->+++++++++<]>++++++++.--
--------.++++++.<+++++++++[->---------<]>----.<++++++++[->++++++++<]>++++.+++++.
-----.++++++++++.<++++++++[->--------<]>-------.<+++++++++[->++++++++<]>+++++.<+
++++++++[->---------<]>---.<++++++++[->++++++++<]>+++++++.--.<+++++[->+++<]>.<++
+++++++[->---------<]>---.<+++++++++[->++++++++<]>+.+++++++++++.<++++++++[->----
----<]>------...--------------.<+++++++[->++++++<]>+.<+++++[->+++++<]>+..+++++++
++++.<++++++++++[->--------<]>.<+++++++++[->+++++++++<]>+++.--.+++++++.<++++[->-
---<]>.+++++.-------.<++++++++[->--------<]>------.<[-]>[-]+<]>-[[-]>[-]<+++++++
+[->++++++++<]>+++.<+++++++[->++++++<]>++.-.-------.+++++++++++.<++++[->----<]>-
.<++++[->++++<]>+++.++++++.<+++++++++[->---------<]>--------.-.<++++++++[->+++++
++<]>+.<+++++[->++++<]>++.++++++.<+++++++++[->---------<]>----.<++++++++[->+++++
+++<]>+++++++.++++++++.+++++.<+++++++++[->---------<]>---.<+++++++++[->++++++++<
]>+.+++++++++++.<+++++++++[->---------<]>--.<][-]>[-]++++++++++..<++++++++[->+++
+++++<]>++++++.<++++++[->+++++<]>++++.-------------.++++++++++++++..<+++++++++[-
>---------<]>--.<++++++++[->++++++++<]>+.+++++++++++++.+++++++++++.<+++++++++[->
---------<]>--------.<+++++++++[->++++++++<]>+++.------.<+++++[->++++<]>.<++++++
+++[->---------<]>--------.<+++++++++[->+++++++++<]>+++.-----.<+++++++++[->-----
---<]>-------.<++++++++[->++++++++<]>+++.++++++++++++.-.++++++.-----------.+++++
.+++++++.<++++[->----<]>.<+++++++[->-------<]>------...<,

You can convert BF code to C like code without much effort, 'Hyper' is serial.

(Try this: http://www.iwriteiam.nl/Ha_bf_online.html)

Use (or code) your own BF debugger with a memory view can also be a solution instead of learning the language.

Learn more about BF ~

>	Move the pointer to the right
<	Move the pointer to the left
+	Increment the memory cell under the pointer
-	Decrement the memory cell under the pointer
.	Output the character signified by the cell at the pointer
,	Input a character and store it in the cell at the pointer
[	Jump past the matching ] if the cell under the pointer is 0
]	Jump back to the matching [ if the cell under the pointer is nonzer