Blue Coat Systems WinProxy Host Header Stack Overflow Vulnerability
iDefense Security Advisory 01.05.06
http://www.idefense.com/intelligence/vulnerabilities/display.php?id=364
January 05, 2006
I. BACKGROUND
BlueCoat WinProxy is an Internet sharing proxy server designed for small
to medium businesses. In addition to Internet sharing Winproxy also
hosts a series of security, anti-spam and anti-spyware capabilities.
More information can be located from the vendors site at:
http://www.winproxy.com/
II. DESCRIPTION
Remote exploitation of a buffer overflow vulnerability in Blue Coat
Systems Inc.'s WinProxy allows for the remote execution of arbitrary
code by attackers.
The vulnerability can be triggered by sending an overly long Host:
string to the web proxy service.
III. ANALYSIS
Exploitation of this vulnerability is trivial. An overly long header
directly overwrites the SEH handler for the frame allowing for control
over EIP.
IV. DETECTION
iDefense has confirmed this vulnerability in WinProxy 6.0. All previous
versions are suspected to be vulnerable.
V. WORKAROUND
Disabling the WinProxy web proxy protocol will prevent this attack.
VI. VENDOR RESPONSE
Blue Coat has released WinProxy 6.1a to address this vulnerability.
VII. CVE INFORMATION
The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CAN-2005-4085 to this issue. This is a candidate for inclusion in
the CVE list (http://cve.mitre.org), which standardizes names for
security problems.
VIII. DISCLOSURE TIMELINE
12/07/2005 Initial vendor notification
12/08/2005 Initial vendor response
01/05/2006 Coordinated public disclosure
IX. CREDIT
This vulnerability was discovered by FistFuXXer.
Get paid for vulnerability research
http://www.idefense.com/poi/teams/vcp.jsp
Free tools, research and upcoming events
http://labs.idefense.com
X. LEGAL NOTICES
Copyright © 2006 iDefense, Inc.
Permission is granted for the redistribution of this alert
electronically. It may not be edited in any way without the express
written consent of iDefense. If you wish to reprint the whole or any
part of this alert in any other medium other than electronically, please
email customerservice@idefense.com for permission.
Disclaimer: The information in the advisory is believed to be accurate
at the time of publishing based on currently available information. Use
of the information constitutes acceptance for use in an AS IS condition.
There are no warranties with regard to this information. Neither the
author nor the publisher accepts any liability for any direct, indirect,
or consequential loss or damage arising from use of, or reliance on,
this information.
_______________________________________________
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/
