-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

===========================================================================
             AUSCERT External Security Bulletin Redistribution

                    ESB-2007.0030 -- [Win][UNIX/Linux]
                    WordPress multiple vulnerabilities
                              16 January 2007

===========================================================================

        AusCERT Security Bulletin Summary
        ---------------------------------

Product:              WordPress 2.0.5 and prior
Publisher:            Hardened-PHP Project
Operating System:     UNIX variants (UNIX, Linux, OSX)
                      Windows
Impact:               Execute Arbitrary Code/Commands
                      Cross-site Scripting
Access:               Remote/Unauthenticated

Original Bulletin:    http://www.hardened-php.net/advisory_012007.140.html
                      http://www.hardened-php.net/advisory_022007.141.html

Comment: Note that this bulletin contains two advisories regarding WordPress.
         Upgrading to WordPress 2.0.6 fixes both issues.

- --------------------------BEGIN INCLUDED TEXT--------------------

- -----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1


                        Hardened-PHP Project
                        www.hardened-php.net

                      -= Security  Advisory =-


     Advisory: WordPress Trackback Charset Decoding SQL Injection Vulnerability
 Release Date: 2007/01/05
Last Modified: 2007/01/05
       Author: Stefan Esser [sesser@hardened-php.net]

  Application: WordPress <= 2.0.5
     Severity: The support of trackbacks in different charsets can
               be used to bypass WordPress's SQL injection protection.
               This might result in a compromise of the admin
               account and the execution of arbitrary PHP code
               on the server
         Risk: Critical
Vendor Status: Vendor has released WordPress 2.0.6 which fixes this issue
   References: http://www.hardened-php.net/advisory_022007.141.html


Overview:

   Quote from http://www.wordpress.org
   "WordPress was born out of a desire for an elegant, well-
    architectured personal publishing system built on PHP and MySQL 
    and licensed under the GPL. It is the official successor of 
    b2/cafelog. WordPress is fresh software, but its roots and 
    development go back to 2001. It is a mature and stable product. 
    We hope by focusing on user experience and web standards we can 
    create a tool different from anything else out there."

   While testing WordPress it was discovered that WordPress supports
   trackbacks in different charsets when PHP's mbstring extension is
   installed. This feature can be abused to bypass WordPress's SQL
   parameter escaping which leads to an SQL injection vulnerability
   that can result in a compromise of the admin account and end in
   a server compromise.


Details:

   WordPress supports decoding trackbacks with different charsets
   when PHP's mbstring extension is activated. Because the decoding
   happens after the database escaping is performed choosing the
   right charset for the input data allows bypassing the protection
   against SQL injection.
   
   For the demonstration exploit that was shared with the WordPress
   developers the UTF-7 charset was chosen, because it is the
   easiest to work with. Other multibyte charsets that for example
   allow multibyte sequences ending in '\' can also be used.
   
   The exploit first checks if the mbstring extension is loaded by
   sending only an UTF-7 encoded '0' in the title field. Because
   only a decoded '0' will pass the empty() check this will trigger 
   two different error situations depending on mbstring availability.
   
   The exploit continues with injecting bogus SQL commands into the
   SQL query which will result in WordPress giving out detailed
   information about the failed query. This error message is used
   to determine the configure database table prefix, which is needed
   for the correct exploitation.
   
   In the next step a harmless looking bogus comment is injected 
   into the comment table with a timestamp in the future. This is
   done to stop WordPress from sending notification emails to the
   admin during the password hash retrieval.
   
   The rest of the exploit is a simple UNION SELECT injection that
   determines password hashes by issuing a request for every bit of
   the hash (128 bits) and checking which error message is returned.
   With the reconstructed password hash it is possible to create a
   WordPress login cookie that can be used to become admin.
   
   As admin it is possible to edit (overwrite) all files within the 
   blog directory that are writeable. This can be used to inject
   arbitrary PHP code in most installations. There exists a protection
   that denies loading the wp-config.php file into the file editor,
   but it can be tricked by directly sending a POST request that
   only saves the files. The wp-config.php file is usually left 
   writeable after the installation has finished.
   

Proof of Concept:

   The Hardened-PHP Project is not going to release a proof of concept 
   exploit for this vulnerability.


Disclosure Timeline:

   29. December 2006  - Notified security@wordpress.org
   05. January 2007   - WordPress 2.0.6 release
   05. January 2007   - Public Disclosure


Recommendation:

   We strongly recommend to upgrade to WordPress 2.0.6 which also
   fixes several other security vulnerabilities not covered by this
   advisory.
   
   http://wordpress.org/download/


GPG-Key:

   http://www.hardened-php.net/hardened-php-signature-key.asc

   pub  1024D/0A864AA1 2004-04-17 Hardened-PHP Signature Key
   Key fingerprint = 066F A6D0 E57E 9936 9082  7E52 4439 14CC 0A86 4AA1


Copyright 2007 Stefan Esser. All rights reserved.

- -----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.3 (GNU/Linux)

iD8DBQFFnnfrRDkUzAqGSqERArBQAJ9KW5+1EwwTozgtHQJgZR0XMwLLygCglC4n
5/ova+EUrueU++pt6ohD5q0=
=JqSS
- -----END PGP SIGNATURE-----

- -----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1


                        Hardened-PHP Project
                        www.hardened-php.net

                      -= Security  Advisory =-


     Advisory: WordPress CSRF Protection XSS Vulnerability
 Release Date: 2007/01/05
Last Modified: 2007/01/05
       Author: Stefan Esser [sesser@hardened-php.net]

  Application: WordPress <= 2.0.5
     Severity: The CSRF protection of WordPress's administration
               interface is vulnerable to an XSS vulnerability
               which might result in a compromise of the admin
               account and the execution of arbitrary PHP code
               on the server
         Risk: Critical
Vendor Status: Vendor has released WordPress 2.0.6 which fixes this issue
   References: http://www.hardened-php.net/advisory_012007.140.html


Overview:

   Quote from http://www.wordpress.org
   "WordPress was born out of a desire for an elegant, well-
    architectured personal publishing system built on PHP and MySQL 
    and licensed under the GPL. It is the official successor of 
    b2/cafelog. WordPress is fresh software, but its roots and 
    development go back to 2001. It is a mature and stable product. 
    We hope by focusing on user experience and web standards we can 
    create a tool different from anything else out there."

   While testing WordPress it was discovered that there is a XSS
   vulnerability in the CSRF protection of WordPress's administration
   interface. This might result in a compromise of the admin account
   and might result in the execution of arbitrary PHP code.


Details:

   The administration interface within WordPress comes with a token
   based CSRF protection. When a request is received with an invalid
   token it is not discarded like in many similar applications, but
   a warning screen is returned that asks the admin to verify the
   action by clicking on a link (that contains a valid token).
   
   Unfortunately there was a bug in the way the request information
   (URL variables) was put into the new link. Due to this fault it
   was possible to break out of the HTML string context by embedding
   quotes and HTML tags into the names of URL variables. 
   
   Due to this is is possible to launch XSS attacks against admin
   users currently logged into their WordPress and perform all possible
   administrative actions (or simply steal the login cookie). 
   Depending on the file permissions on the server (for example a 
   writeable wp-config.php or template file) this can also be 
   exploited to execute arbitrary PHP code.


Proof of Concept:

   The Hardened-PHP Project is not going to release a proof of concept 
   exploit for this vulnerability.


Disclosure Timeline:

   14. November 2006  - Notified security@wordpress.org
   05. January 2007   - WordPress 2.0.6 release
   05. January 2007   - Public Disclosure


Recommendation:

   We strongly recommend to upgrade to WordPress 2.0.6 which also
   fixes several other security vulnerabilities not covered by this
   advisory.
   
   http://wordpress.org/download/


GPG-Key:

   http://www.hardened-php.net/hardened-php-signature-key.asc

   pub  1024D/0A864AA1 2004-04-17 Hardened-PHP Signature Key
   Key fingerprint = 066F A6D0 E57E 9936 9082  7E52 4439 14CC 0A86 4AA1


Copyright 2007 Stefan Esser. All rights reserved.

- -----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.3 (GNU/Linux)

iD8DBQFFnnflRDkUzAqGSqERAj0FAJ90O0DfF6ETzPOepDmSmERA34OoqwCeIgSP
hGSWX194r0vFm40tMaUc4bQ=
=R3/p
- -----END PGP SIGNATURE-----

- --------------------------END INCLUDED TEXT--------------------

You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to auscert@auscert.org.au
and we will forward your request to the appropriate person.

NOTE: Third Party Rights
This security bulletin is provided as a service to AusCERT's members.  As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content. The decision to follow or act on information or advice
contained in this security bulletin is the responsibility of each user or
organisation, and should be considered in accordance with your organisation's
site policies and procedures. AusCERT takes no responsibility for consequences
which may arise from following or acting on information or advice contained in
this security bulletin.

NOTE: This is only the original release of the security bulletin.  It may
not be updated when updates to the original are made.  If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the author's website to ensure that the information is still current.

Contact information for the authors of the original document is included
in the Security Bulletin above.  If you have any questions or need further
information, please contact them directly.

Previous advisories and external security bulletins can be retrieved from:

        http://www.auscert.org.au/render.html?cid=1980

If you believe that your computer system has been compromised or attacked in 
any way, we encourage you to let us know by completing the secure National IT 
Incident Reporting Form at:

        http://www.auscert.org.au/render.html?it=3192

===========================================================================
Australian Computer Emergency Response Team
The University of Queensland
Brisbane
Qld 4072

Internet Email: auscert@auscert.org.au
Facsimile:      (07) 3365 7031
Telephone:      (07) 3365 4417 (International: +61 7 3365 4417)
                AusCERT personnel answer during Queensland business hours
                which are GMT+10:00 (AEST).
                On call after hours for member emergencies only.
===========================================================================

-----BEGIN PGP SIGNATURE-----
Comment: http://www.auscert.org.au/render.html?it=1967

iQCVAwUBRaw/8yh9+71yA2DNAQL33gP+PY009o7dZqyeXQ0xJEAr5y8LMnckghvz
sQI7WGIMr+a8VNpMzxALV+DIFSKnlRQKR2SUXjrjGI51nzVNDZlu39eOeUlGRJ27
KVW3tD7KtF05jZNzyckeLkri691CkePSEguskLdjpSy3v/VhFRucVONK1eLGGVu4
P3S3mMrT/F4=
=9IhY
-----END PGP SIGNATURE-----