Full Disclosure mailing list archives
Re: Re: file_exists() bypassing , critical problem ?
From: "Nourredine Himeur" <lostnoobs () security-challenge com>
Date: Mon, 2 Feb 2004 12:23:40 +0100
There are various methods for securing file_exists() ...If you want to secure ... so that's unsecure , is'nt it ?I didn't say that file_exists() is secure, did I?
I don't think that is critical problem.If it's not a problem Why you show us a methode to secure ?
I didn't say that it is not a problem but that it is not a critical
problem.
I think many programmers don't know this problem exists ! But there is too much hypocresy in php community to admit this vulnerability.
This is not a PHP vulnerability but a PHP Script vulnerablity, and I am
sure
that many php programmers are aware of security problems while using file_exists().
The article : http://www.zend.com/zend/art/art-oertli.php don't talk about this sorry...
What is the problem, very interesting article, old one but still very interesting.
file_exists() must check if the file exists and with this vulnerabilty it don't do this. For me this function don't work good. re-read it :) °°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°° °°° In the same directory : test.php ----------------------------------------------------------- <? if(file_exists($page)){ echo("Sorry the local page is protected"); }else{ include($page); } ?> ----------------------------------------------------------- file.txt ----------------------------------------------------------- Hello World ----------------------------------------------------------- http://www.example.com/test.php?page=file.txt Result: Sorry the local page is protected http://www.example.com/test.php?page=./[anything]/../file.txt <----------------- the file exists but the function file_exists() don't show it. so the file is include !!!!! Result: Hello World The function file_exists() is bypassing just with ./[anything]/../file.txt the function return wrong but the file exist °°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°° °°° Nourredine Himeur www.security-challenge.com _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.netsys.com/full-disclosure-charter.html
Current thread:
- file_exists() bypassing , critical problem ? Lost Noobs (Feb 02)
- Re: file_exists() bypassing , critical problem ? m.esco (Feb 02)
- <Possible follow-ups>
- file_exists() bypassing , critical problem ? Nourredine Himeur (Feb 02)
- file_exists() bypassing , critical problem ? Nourredine Himeur (Feb 02)
- Re: Re: file_exists() bypassing , critical problem ? Nourredine Himeur (Feb 02)
- Re: Re: file_exists() bypassing , critical problem ? m.esco (Feb 02)
- Re: Re: file_exists() bypassing , critical problem ? Nourredine Himeur (Feb 02)
- Re: Re: file_exists() bypassing , critical problem ? Stefan Esser (Feb 02)
- Re: file_exists() bypassing , critical problem ? Daniel B (Feb 02)
- Re: Re: file_exists() bypassing , critical problem ? m.esco (Feb 02)
- Message not available
- Re: file_exists() bypassing , critical problem ? Nourredine Himeur (Feb 02)
- Re: Re: file_exists() bypassing , critical problem ? VeNoMouS (Feb 02)
- Re: file_exists() bypassing , critical problem ? Jorrit Kronjee (Feb 02)