Re: [Full-Disclosure] Re: php-nuke again ...

[Melvyn Sopacua]

At 09:25 1/21/2003, Pawel Kaczor wrote:

on wed, 15 jan 2003, karol wi�sek wrote:

> snip from mailatach.php
>
> if (isset($userfile) and $userfile != "none") {
>     if (ini_get(file_uploads) and $attachments == 1) {
>       $updir = "tmp";
>       @copy($userfile, "$updir/$userfile_name");
>
> sample attack which allows an attacker to grab database password
> and login.
>
> http://target.server/modules/webmail/mailattach.php?
> userfile=../../config.php&userfile_name=../attachments/file.txt&
> attachments=1

i wasn't able to provide this attack succssefully but there's easy way of
prevention - one can put those lines at the beginning of mailattach.php
file:

if (eregi("mailattach.php",$php_self)) {
    header("location: ../../index.php");
    die();
}

Please - that is not a fix, but a delay of problems. $userfile should be verified
as being an uploaded file. The best way is to break php3 compatibility, drop
the register_globals requirement and use the $_FILES array and/or functions
like is_uploaded_file, which are created for the purpose. This assumes that
the content and extension of the file is not important - ie user-input validation,
which is the general implementation error plagueing php-nuke throughout the
entire source.

Given it's trackrecord, uninstalling php-nuke is probably the longterm solution.


Met vriendelijke groeten / With kind regards,

Webmaster IDG.nl
Melvyn Sopacua

<@Logan> I spent a minute looking at my own code by accident.
<@Logan> I was thinking "What the hell is this guy doing?"

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