How can I get another process base adress in Windows using C#?

Question

I was browsing exploitdb when I found one of Asus old drivers are vulnerable to physical memory read/write. There is a fully working PoC showing how to read from RAM. The problem is that I have an offset (let´s say 0x31E4) that indicates relative position of value that I need in programs memory, but the driver is returning info of absolute windows adress. How can I get base process adress in physical memory (preferebly in C#)? Is it even possible?

Example pseudocode:

DWORD offset = 0x31E4; // Offset
int size = sizeof(float); // Size of float
float output = Read(ProgramBase + offset, size); // Read function that read absolute value from RAM, for that I need ProgramBase

Answer 1

If you want to find starting block of memory and ending block, this code should do it:

  Process p = Process.GetCurrentProcess();
  IntPtr startMemory= p.MainModule.BaseAddress; 
  IntPtr endMemory= IntPtr.Add(startMemory,p.MainModule.ModuleMemorySize);

Ofcourse instead of current process, you can get any other process, for example:

Process.GetProcessById(processId)