Re: WordPress <= 2.8.5 Unrestricted File Upload Arbitrary PHP Code Execution

[Moritz Naumann <security () moritz-naumann com>]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA512

Milan Berger wrote:
> Hi there,
>
> > IV. PROOF OF CONCEPT
> > -------------------------
> > Browser is enough to replicate this issue. Simply log in to your  
> > wordpress blog as a low privileged
> > user or admin. Create a new post and use the media file upload
> > feature to upload a file:
> >
> > test-image.php.jpg
> >
> > containing the following code:
> >
> > <?php
> >      phpinfo();
> > ?>
> >
> > After the upload you should receive a positive response saying:
> >
> > test-vuln.php.jpg
> > image/jpeg
> > 2009-11-11
> >
> > and it should be possible to request the uploaded file via a link:
> > http://link-to-our-wp-unsecured-blog.com/wp-content/uploads/2009/11/test-vuln.php.jpg
>
> tried this with lighttpd and wordpress 2.8.5 and PHP 5.2.11-pl0-gentoo
> with Suhosin-Patch 0.9.7
> Shows a broken image no code executed.

This is specific to Apaches' Add* directives, when combined with the PHP
SAPI / Apache module:
http://httpd.apache.org/docs/2.2/mod/mod_mime.html#multipleext
http://isc.sans.org/diary.html?storyid=6139

It's been like that for years, but many Linux distros still ship with
default configurations which bear this issue.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.10 (GNU/Linux)

iEYEAREKAAYFAkr8SxwACgkQn6GkvSd/BgyWFACcDDGWwp92WxOunIr26u3juxL5
FvYAn1ynPl1pBolZKyV/mLQrb+i/AROY
=sM0Q
-----END PGP SIGNATURE-----

_______________________________________________
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/