Post infection
The shutdown function is executed as follows:
0040211F /. 55 PUSH EBP 00402120 |. 8BEC MOV EBP,ESP 00402122 |. 83EC >SUB ESP,10 00402125 |. 56 PUSH ESI 00402126 |. 8B75 >MOV ESI,DWORD PTR SS:[EBP+8] 00402129 |. 57 PUSH EDI 0040212A |. 33FF XOR EDI,EDI 0040212C |. 57 PUSH EDI 0040212D |. 8D86 >LEA EAX,DWORD PTR DS:[ESI+58E] 00402133 |. 50 PUSH EAX 00402134 |. FF96 >CALL DWORD PTR DS:[ESI+394] ;kernel32.WinExec
With parameters:
Nopping that part out (select the code area in the CPU window, press space, type nop
in the dialog box, and then press Enter), so that it does not execute, we reach:
0040213A |. 68 10>PUSH 2710 0040213F |. FF96 >CALL ...
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