The game checks to see if patches (a patch) was modified. Not only that, but it does multiple checks against the server to confirm nothing was tampered. It has so much encryptions that you just don't wanna hack it no more. Take it from me that you all are just wasting your time. Go back to Black Ops and make patches online. That's easier than what you don't know is going on in the game. Here is a function that I recreated from the game that load scripts. The scripts, of course, are located inside the fastfiles.
Originally posted by another user
LoadPatchFiles proc inFile: DWORD
mov eax, inFile
push 1
push eax
push 19h
call LoadPatchFilesFXN
ret
LoadPatchFiles endp
I think I can release this exploit here as well. Modern Warfare 3 uses fairly the same anti-packet modification as Black Ops. To make it simple, you can disable the packet checks then do packet injection. I won't show you how because it could lead to more xp lobbies. The only people who deserve it is the ones who knows how to do it.
(BLACK OPS)
Originally posted by another user
1. Disable the check that the t5mp_ps3f.self do to see if a packet was modified:
008FF76D = nop
008FF76F = nop (i think you nop this)
008FF771 = nop (i think you nop this)
008FF773 = nop (i think you nop this)
2. Disable the check that the t5mp_ps3f.self do to see if the packet has a valid security id:
008FFF55 = nop
3. Disable packet format invalid:
008FEB25 = nop
There is some missing information, but that should give you enough to get it semi-working. Back on to the patches, the game can be hacked (splitscreen), via code injection. This is when the game uses the above function, LoadPatchFiles proc inFile: DWORD, in memory is that file's coding. From that you are able to inject/write your own memory. This part is the funnest

. Coding your own and then detour the LoadPatchFiles function to inject your own script.
The BlackOps game save exploit is possible on MW3 as well. I'm awaiting next MW3 patch to see if they fixed it. Just to note, so you all can see what you're doing before wasting your time. The game does server checks on nearly everything! The encryptions will make your brain poop. The rsa key is like: add dword ptr ds:[edx+037h], dh. You have to find what "dh" is to add it up. However, you could just detour the code to let the game do it for you.
~Odysseus