手脱PE Pack v1.0

1.PEID查壳

PE Pack v1.0

2.载入OD，一上来就这架势，先F8走着

00403235 > /74 00           je short Pepack_1.00403237        ; //入口点
00403237  -\E9 C49D0000     jmp Pepack_1.0040D000
0040323C    0000            add byte ptr ds:[eax],al
0040323E    0000            add byte ptr ds:[eax],al
00403240    0000            add byte ptr ds:[eax],al
00403242    0000            add byte ptr ds:[eax],al
00403244    0000            add byte ptr ds:[eax],al

 

3.走到这里，一个pushad，又是我最喜欢的ESP定律，硬件访问断点，shift+F9一次

0040D000    60              pushad
0040D001    E8 00000000     call Pepack_1.0040D006            ; //ESP
0040D006    5D              pop ebp
0040D007    83ED 06         sub ebp,0x6
0040D00A    80BD 3E050000 0>cmp byte ptr ss:[ebp+0x53E],0x1
0040D011    0F84 48020000   je Pepack_1.0040D25F
0040D017    C685 3E050000 0>mov byte ptr ss:[ebp+0x53E],0x1

 

4.ESP落脚点，这个落脚点是一个大跳转，也是指向OEP的关键跳

0040D270  - FFE0            jmp eax                           ; //ESP落脚点
0040D272    8D85 CE050000   lea eax,dword ptr ss:[ebp+0x5CE]
0040D278    50              push eax                          
0040D279    8DBD D1040000   lea edi,dword ptr ss:[ebp+0x4D1]
0040D27F    53              push ebx
0040D280    57              push edi
0040D281    50              push eax   

 

5.来到OEP，脱壳把

004010CC    55              push ebp                        ;//OEP
004010CD    8BEC            mov ebp,esp
004010CF    83EC 44         sub esp,0x44
004010D2    56              push esi
004010D3    FF15 E4634000   call dword ptr ds:[0x4063E4]      
004010D9    8BF0            mov esi,eax                       
004010DB    8A00            mov al,byte ptr ds:[eax]
004010DD    3C 22           cmp al,0x22
004010DF    75 1B           jnz short Pepack_1.004010FC

 

6.运行，查壳

运行OK，查壳：Microsoft Visual C++ v6.0 SPx