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Denial of Service in WordPress
From: "MustLive" <mustlive () websecurity com ua>
Date: Thu, 27 Jun 2013 20:28:00 +0300
These are Denial of Service vulnerabilities WordPress. Which I've disclosed
two days ago (http://websecurity.com.ua/6600/).
About XSS vulnerabilities in WordPress, which exist in two redirectors, I
wrote last year (http://seclists.org/fulldisclosure/2012/Mar/343). About
Redirector vulnerabilities in these WP scripts I wrote already in 2007 (and
made patches for them). The developers fixed redirectors in WP 2.3, so
Redirector and XSS attacks are possible only in previous versions.
As I've recently checked, this functionality can be used for conducting DoS
attacks. I.e. to make Looped DoS vulnerabilities from two redirectors
(according to Classification of DoS vulnerabilities in web applications
(http://websecurity.com.ua/2663/)), by combining web site on WordPress with
redirecting service or other site. This attack is similar to looping two
redirectors, described in my articles Redirectors' hell and Hellfire for
redirectors. The interesting, that looped redirector
(http://tinyurl.com/hellfire-url), which I've made at 5th of February 2009
for my article Hellfire for redirectors, is still working.
Vulnerable are all versions of WordPress: for easy attack - WP 2.2.3 and
previous versions, for harder attack - WP 3.5.2 and previous versions. The
second variant of attack requires Redirector or XSS vulnerability at the
same domain, as web site on WP.
Denial of Service (WASC-10):
It's needed to create Custom alias at tinyurl.com or other redirector
service, which will be leading to wp-login.php or wp-pass.php with setting
alias for redirection.
Here are examples of these vulnerabilities:
This attack will work for WordPress < 2.3. At that Mozilla, Firefox, Chrome
and Opera will stop endless redirect after series of requests, unlike IE.
To make this attack work in all versions of the engine, including WordPress
3.5.2, it's needed that redirector was on the same domain, as web site on
WP. For this it can be used any vulnerability, e.g. reflected XSS or
persistent XSS (at the same domain), for including a script for redirecting
to one of these redirectors:
This attack will work as in WordPress 3.5.2 and previous versions, as it
isn't stopping by the browsers (endless redirect).
Best wishes & regards,
Administrator of Websecurity web site
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