WordPress Link Library 5.9.12.29 Cross Site Scripting

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Cross-Site Scripting in Link Library WordPress Plugin  
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Burak Kelebek, July 2016  
  
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Abstract  
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A Reflected Cross-Site Scripting (XSS) vulnerability has been found in  
the Link Library plugin. By using this vulnerability an attacker can  
inject malicious JavaScript code into the application, which will  
execute within the browser of any logged-in admin.  
  
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OVE ID  
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OVE-20160724-0016  
  
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Tested versions  
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This issue was successfully tested on Link Library version 5.9.12.29.  
  
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Fix  
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This issue is fixed in version 5.9.12.30  
  
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Details  
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https://sumofpwn.nl/advisory/2016/cross_site_scripting_in_link_library_wordpress_plugin.html  
  
Cross-Site Scripting (XSS) attacks are a type of injection, in which malicious scripts are injected into otherwise benign and trusted web sites. XSS attacks occur when an attacker uses a web application to send malicious code, generally in the form of a browser side script, to a different end user. Flaws that allow these attacks to succeed are quite widespread and occur anywhere a web application uses input from a user within the output it generates without validating or encoding it. Reflected XSS occurs when user input is immediately returned by a web application in an error message, search result, or any other response that includes some or all of the input provided by the user as part of the request  
  
"successimportcount" and "sucessupdatecount" fields do not validate <script> tags and do not perform output encoding.  
  
/link-library/link-library-admin.php  
  
885: echo echo "<div id='message' class='updated fade'><p><strong>" . ($_GET['successimportcount'] : '0') . " " . __('link(s) imported', 'link-library') . ", " . ($_GET['successupdatecount'] : '0') . " " . __('link(s) updated', 'link-library') . ".</strong></p></div>";  
  
Proof of concept  
  
http://<targetsite>/wp-admin/admin.php?page=link-library-settingssets&messages=9&successimportcount=1" /><script>alert(1)</script>&currenttab=importexport  
  
  
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Summer of Pwnage (https://sumofpwn.nl) is a Dutch community project. Its  
goal is to contribute to the security of popular, widely used OSS  
projects in a fun and educational way.  
  
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