0

I am trying to learn more about how to read process memory. So I opened the "entire memory" of the Firefox process in WinHex and saw the following hex values starting at offset 10000. 

00 00 00 00 00 00 00 00 EC 6B 3F 80 0C 6D 00 01 EE FF EE FF 01 00 00 00

My question is Is it possible for a human to interpret this without further knowledge? Are these pointers or values? Is there anything, which is common for different programs created with different compilers with regards to the process memory apart from things like endianness? Why does it start with lots of zeroes, isn't that a very odd way to start using space?

David
  • 4,786
  • 11
  • 52
  • 80

1 Answers1

3

Obviously, you can't do anything "without further knowledge". But we already know a whole lot from the fact that it's Windows. For starters, we know that the executable gets its own view of memory, and in that virtual view the executable is loaded at its preferred starting address (as stated in the PE header of the EXE).

The start at 0x00010000 is a compatibility thing with MS-DOS (yes, that 16 bit OS) - the first 64KB are reserved and are never valid addresses. The pages up to 0x00400000 (4MB) are reserved for the OS, and in general differ between OS versions.

A common data structure in that range is the Process Environment Block. With the WinDBG tool, and the Microsoft Symbol Server, you can figure whether the Process Envirionment Block is indeed located at offset 0x10000, and what its contents mean.

MSalters
  • 173,980
  • 10
  • 155
  • 350