Check Point Zone Labs SRESCAN IOCTL Local Privilege Escalation Vulnerability

iDefense Security Advisory 04.20.07
http://labs.idefense.com/intelligence/vulnerabilities/
Apr 20, 2007

I. BACKGROUND

Zone Alarm products provide security solutions such as anti-virus,
firewall, spy-ware, and ad-ware protection. The srescan.sys device
driver contains the Spyware Removal Engine portion of these products.
More information is available at the Zone Labs web site at the
following URL.

http://www.zonelabs.com/

II. DESCRIPTION

Local exploitation of multiple design error vulnerabilities within
multiple Check Point Zone Alarm products could allow an attacker to
gain elevated privileges.

The problem specifically exists within the IOCTL handling code in the
srescan.sys device driver. The device driver fails to validate
user-land supplied addresses passed to IOCTL 0x22208F and IOCTL
0x2220CF.

Since the Irp parameters are not correctly validated, an attacker could
utilize this IOCTL to overwrite arbitrary memory. In the case of IOCTL
0x2220CF, the attacker can write the constant double-word value of
0x30000. In the case of IOCTL 0x22208F, the attacker can write the
contents of a buffer returned from ZwQuerySystemInformation.

III. ANALYSIS

Exploitation allows an attacker to execute arbitrary code within the
context of the kernel.

The access control mechanisms under a default installation allow
restricted accounts to access the affected device drivers. This allows
elevation of privileges directly to SYSTEM.

IV. DETECTION

iDefense has confirmed the existence of these vulnerabilities within
version version 5.0.63.0 of srescan.sys as installed with Check Point
Zone Labs Zone Alarm Free. All other products within the Zone Alarm
product line are suspected to be vulnerable. Previous versions are also
suspected to be vulnerable.

V. WORKAROUND

Changing the access control mechanisms for the affected device drivers
will prevent exploitation by restricted accounts.

VI. VENDOR RESPONSE

The Zone Labs Security Team reports that these issues are "fixed in
versions 5.0.156.0 of the ZoneAlarm Spyware Removal Engine (SRE) and
higher. The currently deployed version of SRE in ZoneAlarm is
5.0.162.0."

VII. CVE INFORMATION

A Mitre Corp. Common Vulnerabilities and Exposures (CVE) number has not
been assigned yet.

VIII. DISCLOSURE TIMELINE

12/19/2006  Initial vendor notification
12/20/2006  Initial vendor response
03/21/2007  Second vendor notification
03/22/2007  Second vendor response
04/20/2007  Coordinated public disclosure

IX. CREDIT

This vulnerability was reported to iDefense by Ruben Santamarta of
reversemode.com.

Get paid for vulnerability research
http://labs.idefense.com/methodology/vulnerability/vcp.php

Free tools, research and upcoming events
http://labs.idefense.com/

X. LEGAL NOTICES

Copyright © 2007 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 e-mail 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.