Snorby 2.6.2 - Stored Cross-site Scripting Vulnerability

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Snorby 2.6.2 - Stored Cross-site Scripting Vulnerability
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Vendor
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https://www.snorby.org/


Version
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2.6.2


Description
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During my research and testing of new IDS (Intrusion Detection System)
like Suricata, I've
found a Stored Cross-site Scripting (XSS) vulnerability in Snorby (that
I'd like to use as
web user interface for suricata). The vulnerability exists in the module
for adding a new
threat classification model where the user input is not correctly
sanitized before being
saved it on the database or for example the output is not properly
filtered, before its
rendering in the event/menu code, in this way the vector gets executed.


Vulnerability
-------------

The output from the page snorby/app/views/events/_menu.html.erb is not
properly sanitized
before its rendering:

--_menu.html.erb--
<% @classifications.each do |cls| %>
    <% if cls.locked && cls.hotkey %>
        <%= drop_down_item "#{cls.name}#{cls.shortcut}", '#', nil, {
:class => 'classification', :"data-classification-id" => cls.id.to_i } %>
    <% else %>
        <%= drop_down_item "#{cls.name}", '#', nil, { :class =>
'classification', :"data-classification-id" => cls.id.to_i } %>
    <% end %>
<% end %>
--end--


Mitigation
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A simple XSS mitigation on rails could be the usage of the sanitize, for
example the code
below filters the xss vector by removing the onerror attribute from the
image tag:

--_menu.html.erb--
<% @classifications.each do |cls| %>
    <% if cls.locked && cls.hotkey %>
        <%= drop_down_item "#{sanitize cls.name}#{cls.shortcut}", '#',
nil, { :class => 'classification', :"data-classification-id" =>
cls.id.to_i } %>
    <% else %>
        <%= drop_down_item "#{sanitize cls.name}", '#', nil, { :class =>
'classification', :"data-classification-id" => cls.id.to_i } %>
    <% end %>
<% end %>
--end--


Solution
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Update to the latest version on Github.


Disclosure
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30-06-2015 – Vendor notification
(https://github.com/Snorby/snorby/issues/377)
30-06-2015 – CVE id requested
01-07-2015 - Vendor acknowledgement
01-07-2015 - Vendor pushed a fix (commit-id:
https://github.com/Snorby/snorby/commit/89d7cbcd3697c8a842f1a61b99e9a78f295798fb)


Credits
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Federico Fazzi - federico.fazzi@gmail.com
Web: http://deftcode.ninja