Cross-Referencing Linux vulnerability

[Albert Puigsech Galicia <ripe () 7a69ezine org>]

Info.
-----

        + Type:         To gain visibility

        + Software:     Cross-Referencing Linux.
         
        + Verions:      until 0.9.2     

        + Exploit:              Si.

        + Autor:                Albert Puigsech Galicia

        + Contact:      ripe () 7a69ezine org





Introduction.
-------------

        Cross-Referencing Linux, as known as LXR, allow read all linux kernel
source using a web navigator. The aplication is writen using Perl languaje, 
and convert to HTML all linux kernel sources. For more information visit the
project's oficial website on http://lxr.linux.nu.



Description.
------------

        LXR suports to navigate through various kernel version. The version is
readed from 'v' variable, witch content are placed in the path used to open
the file without filter the '..' special directory.



Exploiting.
-----------

        In posible to read any file on systema as apache privileges getting up
on tree directory sending malicious data to 'v' variable. Is necessary too, to
finish the path with nul char to ignore the rest of the path, so we add %00 at
the end of 'v'.

        An example of exploit call may be:

        http://vulnerable/source?v=../../../../../../../etc/password%00



Patch.
------

        There aren't an oficial patch for a moment, but is too easy to put a 
regex filtering the '..' content when 'v' variable is read.


--
> =====================
> Albert Puigsech Galicia
>
> http://ripe.7a69ezine.org
> =====================