Cross-site Scriptiang (XSS) / HTML injection on F5 FirePass 4100 SSL VPN 'my.activation.php3' server-side script
19 June 2007
Adrian Pastor and Jan Fry of ProCheckUp Ltd (www.procheckup.com). With thanks to Petko D. Petkov for suggesting the eval(name) technique.
F5 Networks FirePass 4100 SSL VPN is vulnerable to XSS within the "my.activation.php3" server-side script.
No authentication is required to exploit this vulnerability.
An attacker may be able to cause execution of malicious scripting code in the browser of a user who visits a specially-crafted URL to an F5 Firepass device, or visits a malicious page that makes a request to such URL. Such code would run within the security context of the target domain.
This type of attack can result in non-persistent defacement of the target site, or the redirection of confidential information (i.e. admin session IDs) to unauthorised third parties.
Successfully tested on
F5 Networks has confirmed the following versions to be vulnerable:
FirePass versions 5.4.1 - 5.5.2
FirePass versions 6.0 - 6.0.1
Proof of concept:
The payload in the example is
which injects a 'textarea' box
%29%3C/script%3E%3C%21-- " width ="0%" height="0%" name="xss=document.body.appendChild
Successfully tested on:
F5 FirePass 4100
Microsoft Internet Explorer 7.0.5730.11
How to fix:
F5 Networks has issued SOL7923:
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