Simple C++/CLI Crackme x64bit

Your goal is to crack the file and make a tutorial and/ or write instructions about the steps done by you.

What is C++/CLI?

C++/CLI is C++ support .NET framework to make managed application run on .NET framework.

https://en.wikipedia.org/wiki/C%2B%2B/CLI

Feel free to post your solutions.

 

File Information

Submitter SuperJackAbcd

Submitted 01/26/2022

Category CrackMe

View File

Code is pretty readable in richTextBox1_TextChanged where the main keycheck is.

The algorithm:

SHA256(GetComputerNameA(LPSTR, LPDWORD) + "abcdef").ToUpper()

 

my solution:

1.open program file by dnspy
2.find Form1::richTextBox1_TextChanged
3.you can see this:
            if (0 > num6)
            {
                sbyte* ptr4 = ref $ArrayType$$$BY0BAA@D2;
                sbyte* ptr5 = ref $ArrayType$$$BY0DOI@D2;
                while (*ptr5 == *ptr4)
                {
                    num5++;
                    ptr5 += 1L;
                    ptr4 += 1L;
                    if (num5 >= num6)
                    {
                        goto IL_1A9;
                    }
                }
                this.label1.Text = "License key is invalid";
                goto IL_1CB;
            }
            IL_1A9:
            this.label1.Text = "Thank license key is valid.";
4. edit il codes, change 188 bge.s 215(01A9) ldarg.0 to ble.s, save this module. you input anything, it will show you:Thank license key is valid.