CSAW CTF 2013 - Reversing100 (DotNet)

DotNet - 100 Points

DotNetReversing.exe

DotNet is a .Net executables. Let's decompile the executable:

To solve this challenge, one must get the correct value of num in order to get the value of num3=6553563335L. XOR, as we know it, is reversible, so:

num ^ num2 = num3

We can get the value of num by performing:

num = num3 ^ num2

num = 13371337255

Now we run the executable with 13371337255 as the argument:

Flag: I'll create a GUI interface using visual basic...see if I can track an IP address.