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Citrix NetScaler VPX help pages are vulnerable to Cross-Site Scripting
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Han Sahin, August 2014

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Abstract
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It was discovered that the help pages of Citrix VPX are vulnerable to
Cross-Site Scripting. This issue allows attackers to perform a wide
variety of actions, such as stealing the victim's session token or login
credentials, performing arbitrary actions on the victim's behalf, and
logging their keystrokes.

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Tested version
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This issue was discovered in Citrix NetScaler VPX NSVPX-ESX-10.5-50.10,
other versions may also be vulnerable.

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Fix
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Citrix reports that this vulnerability is fixed in NetScaler 10.5 build
52.8nc.

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Details
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https://www.securify.nl/advisory/SFY20140807/citrix_netscaler_vpx_help_pages_are_vulnerable_to_cross_site_scripting.html

This issue exists because the value of the searchQuery URL parameter is assigned client-side to contentDiv.innerHTML (DOM-based Cross-Site Scripting), for example:

https://<target>/help/rt/large_search.html?searchQuery=<h1>Reset your password below:<h1><iframe src='http://www.evil.com'/>&type=ctxTV

Tricking a victim into visiting a specially crafted URL allows attackers to run arbitrary client-side scripting code within the victim's browser. The attacker-supplied code can perform a wide variety of actions, such as stealing the victim's session token or login credentials, performing arbitrary actions on the victim's behalf, and logging their keystrokes.