PR09-04 - Cross-Site Scripting on Portwise SSL VPN v4.6

Vulnerability found:

25 March 2009

Vendor informed:

28 April 2009

Severity level:

Medium

Credits:

George Christopoulos and Jan Fry of ProCheckUp Ltd

Description:

The Portwise portal login page is vulnerable to XSS. Portwise is a
SSL-VPN portal.

Note: Other version might be affected as well

Proof of concept:

The following demonstrate XSS:

1) Login page XSS
https://example.com/wa/auth?&authmech=Assess&reloadFrame=%22;%3Cscript%3Eblah%3C/script%3E%3Cscript%3Ealert(document.cookie)%3C/script%3E

Consequences:

An attacker may be able to cause execution of malicious scripting code
in the browser of a user who clicks on a link to a Portwise Portal-based
site. 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.: session IDs) to
unauthorised third parties.

How to fix:

Ensure all input parameters (especially "reloadFrame") are filtered
sufficiently before beign echoed back to the client.

Legal:

Copyright 2009 Procheckup Ltd. All rights reserved.

Permission is granted for copying and circulating this Bulletin to the Internet community for the purpose of alerting them to problems, if and only if, the Bulletin is not edited or changed in any way, is attributed to Procheckup, and provided such reproduction and/or distribution is performed for non-commercial purposes.

Any other use of this information is prohibited. Procheckup is not liable for any misuse of this information by any third party