Public Vulnerability Reports

Computer Associates eTrust EZ Antivirus Insecure File Permission Vulnerability

12.15.04

BACKGROUND

Computer Associates eTrust EZ Antivirus is antivirus protection software
for home use. It provides complete protection, detection and elimination
of thousands of computer viruses, worms, and Trojan Horse programs.

DESCRIPTION

Local exploitation of an insecure permission vulnerability in Computer
Associates eTrust EZ Antivirus allows attackers to escalate privileges
or disable protection.

Computer Associates eTrust EZ Antivirus is a product used to protect a
personal computer from virus infections. The vulnerability specifically
exists in the default file Access Control List (ACL) settings that are
applied during installation. When an administrator installs eTrust EZ
Antivirus, the default ACL allows any user to modify the installed
files. Because of the fact that some of the programs run as system
services, a user can simply replace an installed eTrust EZ Antivirus
file with their own malicious code that will later be executed with
system privileges. One such file that would be a target for this is
VetMsg.exe.

ANALYSIS

Successful exploitation allows local attackers to escalate privileges to
the system level. It is also possible to use this vulnerability to
simply disable protection by moving all of the executable files so that
they cannot start upon a reboot.

DETECTION

iDEFENSE has confirmed the existence of this vulnerability in eTrust EZ
Antivirus version 7.0.1.4. According to Computer Associates, eTrust EZ
Antivirus r7.0.0 - r7.0.4 installed on PC's running Windows NT, 2000 or
XP and with NTFS formatted drives are also affected.

WORKAROUND

Apply proper Access Control List settings to the directory that eTrust
EZ Antivirus is installed in. The ACL rules should make sure that no
regular users can modify files in the directory.

VENDOR RESPONSE

"With the assistance of iDEFENSE, Computer Associates has identified a
medium-risk vulnerability in the installation and updating components of
eTrustTM EZ Antivirus which may allow a local user to escalate their
user privileges on a PC and disable protection.

Effected generally available releases of eTrust EZ Antivirus include:
eTrust EZ Antivirus r7.0.0 - r7.0.4 installed on PC's
 - running Windows NT, 2000 or XP
 - with NTFS formatted drives

Computer Associates has actively addressed this issue in eTrust EZ
Antivirus r7.0.5 and above.

More information about this vulnerability and instructions on how to
upgrade to the latest version of eTrust EZ Antivirus can be found at:

http://crm.my-etrust.com/login.asp?username=guest&target=DOCUMENT&openparameter=2222

At Computer Associates, we take every report of exposure with the utmost
urgency, to ensure that no customer is left in a vulnerable situation.
We have assigned this vulnerability the ID number 32054."

CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has assigned the
names CAN-2004-1149 to these issues. This is a candidate for inclusion
in the CVE list (http://cve.mitre.org), which standardizes names for
security problems.

DISCLOSURE TIMELINE

12/02/2004   Initial vendor notification
12/02/2004   Initial vendor response
12/15/2004   Coordinated public disclosure

CREDIT

The discoverer of this vulnerability wishes to remain anonymous.

Get paid for vulnerability research
http://www.idefense.com/poi/teams/vcp.jsp

LEGAL NOTICES

Copyright © 2004 Verisign, 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.