New Asprotect?

[hobgoblin]

I just found this one at the RCE forum. The poster asked for people to try to unpack it, so I figured I could post it here (without stepping on someones toes). Anybody capable of unpacking it?

yes i can... and i just did

93k -> 1MB

and i see whoever protected it did not use the EP redirection. wouldn't have mattered tho.

Please keep in mind that this will only work on my machine, or possibly only on the OS in which I unpacked it. As it contains the aspr envelope attached to the dump, I will not post it for possible security reasons, nor do I recommend anyone posting their own dump with the aspr envelope attached.

---edit---
oops, forgot to trim down the size of my aspr envelope had a bunch of 00's.
once trimmed is only 229k. i'm not uploading another jpg. just thought i'd clear that up.

[Computer_Angel]

this "unpackme" is protected with asprotect 1.31 beta, and the poster not using the option hide OEP (to make it unpack easier? ).
I've see nothing in your picture, just a lordpe screen.
With lordpe i can dump it too, but can't fix the IAT, any ideal ?

i'm not posting the file cuz it contains the aspr envelope, which could possible contain other info. but if you must know here is the unpacked oep:

00401000 > 6A 00 PUSH 0
00401002 E8 C1030000 CALL 004013C8
00401007 A3 C0314000 MOV DWORD PTR DS:[4031C0],EAX
0040100C 6A 00 PUSH 0
0040100E 68 2B104000 PUSH 0040102B
00401013 6A 00 PUSH 0
00401015 68 00304000 PUSH 00403000 ; ASCII "MainDialog"
0040101A FF35 C0314000 PUSH DWORD PTR DS:[4031C0]
00401020 E8 73030000 CALL 00401398
00401025 50 PUSH EAX
00401026 E8 97030000 CALL 004013C2 ; JMP to kernel32.ExitProcess
0040102B 55 PUSH EBP
0040102C 8BEC MOV EBP,ESP
0040102E 817D 0C 10010000 CMP DWORD PTR SS:[EBP+C],110
00401035 0F85 8E000000 JNZ 004010C9
0040103B FF75 08 PUSH DWORD PTR SS:[EBP+8]
0040103E 8F05 C4314000 POP DWORD PTR DS:[4031C4]
00401044 51 PUSH ECX
00401045 33C9 XOR ECX,ECX
00401047 51 PUSH ECX
00401048 8D81 28304000 LEA EAX,DWORD PTR DS:[ECX+403028]
0040104E 50 PUSH EAX
0040104F 6A 00 PUSH 0
00401051 68 43010000 PUSH 143
00401056 68 B80B0000 PUSH 0BB8
0040105B FF75 08 PUSH DWORD PTR SS:[EBP+8]
0040105E E8 4D030000 CALL 004013B0
00401063 59 POP ECX
00401064 83C1 05 ADD ECX,5
00401067 81F9 9B000000 CMP ECX,9B
0040106D ^ 75 D8 JNZ SHORT 00401047
0040106F 59 POP ECX
00401070 6A 00 PUSH 0
00401072 6A 00 PUSH 0
00401074 68 4E010000 PUSH 14E
00401079 68 B80B0000 PUSH 0BB8
0040107E FF75 08 PUSH DWORD PTR SS:[EBP+8]

I showed the lordpe screenshot to show it running and the size of the process.

[Computer_Angel]

hi,
unpack is easy, but do you try to fixed iat yet ?
This prog is small, and not contain many api, so you can solve it easily, but think when there's a lot of api, at that time, what can we do now

[hobgoblin]

Hi guys,
Why don't you guys in a few words explain how you unpacked it and fixed the iat?

regards,

Originally Posted by hobgoblin

Hi guys,
Why don't you guys in a few words explain how you unpacked it and fixed the iat?

regards,

To keep it as few words as possible, I'll simply explain the method by which you can unpack and run this version. If you're not familiar with aspr or the pe file format then the following will not help you.

Get to OEP as usual, break on many exceptions and jump over the last exception and RET which will eventually lead you to EP. Then you can dump, that's the easy part. Then what you must do is dump the ASPR envelope from memory and attach it to your dump. I have seen regular sized apps with big import tables and at the moment I have no way of fixing or creating and iat. Once you've attached your ASPR to your dump you need to fix the import table to point to the proper thunks.

That's the extreme basic way of doing it

There are things you can do to change the ASPR envelope's native address, etc. Plus lots of cleaner ways to rebuild your pe. But that right there is the basic idea.

Also note that this approach will only allow the dump to run on your machine or possibly only the same os. It's definitely not a cross-platform solution with a generic iat/import table. But it works nonetheless.

One other thing to mention. Since this version does not use the native iat to point to system apis or redirected apis it will be quite a task to create an iat and that, really, is the only stumbling block for a more 'pure' solution. The other things such as obfuscated redirected functions are quite a bit tougher with this version, but that can always be resolved by simply attaching the obfuscated code somewhere and redirecting the jump/call to it.

I hope that answers some questions