Revision History
2/9/2005 - Updated Vulnerability details and mitigations. Updated CVE Candidate Number
2/11/2005 – Configuration modifications tested and added to disable vulnerable module in SAVCE and SCS. URL to Technical Support KB with details.
2/17/2005 - Further breakout to clarify vulnerable and non-vulnerable builds.

Risk Impact
High

Overview
Symantec resolved a potential remote access compromise vulnerability reported by ISS X-Force. The vulnerability was identified in an early version of a Symantec antivirus scanning module responsible for parsing UPX compressed files that is still in limited use in some Symantec security products.

The vulnerable component fails to do proper bounds checks when analyzing certain container files for virus content. An attacker sending a specifically crafted UPX file could potentially compromise the targeted system.

NOTE: Users of affected products should ensure they are running a non-vulnerable product build or have installed recommended hotfixes.

If unable to update at this time, customers should implement the configuration procedures to disable the affected DEC2EXE module in those products, Symantec BrightMail, Symantec AntiVirus Corporate Edition and Symantec Client Security that are configurable, as documented in this advisory and associated product support Knowledge Base.

Symantec has NOT seen any active attempts against or organizations impacted by this issue. However, Symantec Security Response created Bloodhound.Exploit.26, a heuristic detection for attempts to exploit the DEC2EXE.dll heap overflow vulnerability. Virus definitions version 70209af (extended version 2/9/2005 rev. 32) or greater contain this heuristic and are available through Symantec LiveUpdate or Symantec's Intelligent Updater.

Vulnerable Products (vulnerable builds/Maintenance Releases (MR) where indicated)
Enterprise Products

Consumer Products

Symantec Norton Antivirus 2004 for Windows
Symantec Norton Internet Security 2004 (pro) for Windows
Symantec Norton System Works 2004 for Windows

Non-Vulnerable Products (initial non-vulnerable build/Maintenance Release (MR) where indicated)
Enterprise Products

Norton AntiVirus for Microsoft Exchange 2.18	build 82 and earlier
Norton AntiVirus for Microsoft Exchange 2.18	build 85
Norton AntiVirus for Microsoft Exchange 2.18	build 88
Symantec Mail Security for Microsoft Exchange 4.0	build 456 and earlier
Symantec Mail Security for Microsoft Exchange 4.0	build 463
Symantec Mail Security for Microsoft Exchange 4.0	build 465
Symantec Mail Security for Microsoft Exchange 4.5	build 736
Symantec Mail Security for Microsoft Exchange 4.5	build 741
Symantec Mail Security for Microsoft Exchange 4.5	build 743
Symantec Mail Security for Microsoft Exchange 4.6	build 97
Symantec AntiSpam for SMTP 3.1	All
Symantec AntiVirus/Filtering for Domino NT 3.1	All
Symantec Mail Security for Domino 4.0	build 4.0.1
Symantec Mail Security for Domino 4.1	All
Symantec AntiVirus/Filtering for Domino Ports 3.0
(S390)	All
(AIX)	Prior to build 3.0.5
(AIX)	3.0.6
(OS400, Linux, Solaris)	Prior to build 3.0.5
(OS400, Linux, Solaris)	build 3.0.7
Symantec AntiVirus Scan Engine 4.3	build 4.3.3
Symantec AntiVirus Scan Engine for ISA 4.3.X	build 4.3.3
Symantec AntiVirus Scan Engine for Netapp Filer 4.3.X	build 4.3.3
Symantec AntiVirus Scan Engine for Netapp NetCache 4.3.X	build 4.3.3
Symantec AntiVirus for Caching	build 4.3.3
Symantec AntiVirus Scan Engine for Microsoft Portal Server 4.3.X	All
Symantec AntiVirus Scan Engine for Bluecoat 4.3.X	build 4.3.3
Symantec AntiVirus Scan Engine for Filers 4.3.X	build 4.3.3
Symantec AntiVirus for Microsoft Office	All
SharePoint Portal Server 2003	All
Symantec AntiVirus for SMTP 3.0	build 3.0.0.29
Symantec AntiVirus for SMTP 3.1	build 3.1.7
Symantec Mail Security for SMTP 4.0	build 4.0.2
Symantec Mail Security for SMTP 4.1	All
Symantec Web Security 3.01.x	Prior to build 3.01.59
Symantec Web Security 3.01.x	build 3.0.1.70
Symantec Web Security 3.01.x	build 3.0.1.72
Symantec BrightMail AntiSpam 6.0	All
Symantec BrightMail AntiSpam 4.0     (Disable DEC2EXE per mitigation instructions)
Symantec BrightMail AntiSpam 5.5     (Disable DEC2EXE per mitigation instructions)
Symantec AntiVirus Corporate Edition 9.0	STM build 9.0.0.338 (module installed but not loaded into memory)
Symantec AntiVirus Corporate Edition 9.0	MR 1 build 9.0.1.1000
Symantec AntiVirus Corporate Edition 9.0	MR 2 build 9.0.2.1000
Symantec AntiVirus Corporate Edition 9.0	MR 3 build 9.0.3.1000
Symantec AntiVirus Corporate Edition 8.1.1	build 8.1.0.825a
Symantec AntiVirus Corporate Edition 8.1.1	build 8.1.1.366
Symantec AntiVirus Corporate Edition 8.0	build 8.01.9374
Symantec AntiVirus Corporate Edition 8.0	build 8.01.9378
Symantec AntiVirus Corporate Edition 8.0	build 8.01.425a/b
Symantec AntiVirus Corporate Edition 8.0	build 8.01.429c
Symantec AntiVirus Corporate Edition 8.0	build 8.01.501
Symantec Client Security 2.0	STM build 9.0.0.338 (module installed but not loaded into memory)
Symantec Client Security 2.0.1	MR1 build 9.0.1.1000
Symantec Client Security 2.0.2	MR2 build 9.0.2.1000
Symantec Client Security 2.0.3	MR3 build 9.0.3.1000
Symantec Client Security 1.1	Initial STM Release build 8.1.0.825a
Symantec Client Security 1.1.1	MR6 build 8.1.1.266
Symantec Client Security 1.0	build 8.01.9374
Symantec Client Security 1.0.0	build 8.01.9378
Symantec Client Security 1.0.1	MR1 build 8.01.425a/b
Symantec Client Security 1.0.1	MR2 build 8.01.429c
Symantec Client Security 1.0.1	MR9 build 8.01.501
Symantec Norton AntiVirus 7.6     (does not install the vulnerable module)
Symantec Mail-Gear
Symantec I-Gear
Symantec AntiVirus for HandHelds - Corporate Edition (does not install the DEC2EXE module)
Symantec Client Security for Nokia Communicator (does not install the DEC2EXE module)

Consumer Products
Symantec Norton Antivirus 2003
Symantec Norton Internet Security 2003 (pro)
Symantec Norton System Works 2003
Symantec Norton AntiVirus 2005
Symantec Norton Internet Security 2005
Symantec Norton System Works 2005 (Premier)
Symantec Norton Antivirus 7.x for Macintosh
Symantec Norton Antivirus 8.x for Macintosh
Symantec Norton Internet Security 2.x for Macintosh
Symantec Norton System Works 7.0 for Macintosh

Details
ISS X-Force notified Symantec of a vulnerability discovered in the DEC2EXE parsing engine module used in earlier versions of the Symantec scan engine. The vulnerable DEC2EXE engine contained a heap overflow that could be initiated by sending a specifically crafted UPX file that would be parsed by the vulnerable DEC2EXE engine. If successfully exploited, the attack could potentially result in remote arbitrary code execution and possible compromise of the targeted system.

Symantec Response
Symantec confirmed the vulnerability ISS identified in the original DEC2EXE engine. The DEC2EXE engine is no longer required to parse compressed files. Prior to ISS contacting Symantec with this vulnerability, Symantec had already removed the DEC2EXE engine from the scan engine upgrades implemented in the majority of Symantec products.

Symantec has NOT seen any active attempts against or organizations impacted by this issue. However, Symantec Security Response created Bloodhound.Exploit.26, a heuristic detection for attempts to exploit the DEC2EXE.dll heap overflow vulnerability. Virus definitions version 70209af (extended version 2/9/2005 rev. 32) or greater contain this heuristic and are available via Symantec LiveUpdate or Symantec's Intelligent Updater.

Recommended Upgrades
As a part of normal best practices, users should keep vendor-supplied patches for all application software and operating systems up-to-date. Symantec strongly recommends customers, if they are not already running a current non-vulnerable product version/build, upgrade to their appropriate product update immediately to protect against these types of threats.

Symantec product engineers have developed and released updates or Maintenance Releases for all impacted product versions that were not already upgraded in the latest product build release. Updates and Maintenance Releases are available either through Symantec's LiveUpdate for those products that have LiveUpdate capability or from the Symantec Product Support site at http://www.symantec.com/techsupp.

	Symantec Gateway Security 5300/5400 Series: 

Mitigation:

	
	Symantec BrightMail AntiSpam versions 4.0 and 5.5
	

	For Solaris and Linux:
	
	1. Locate brightmail.cfg . 
	   The default location for this file is /opt/mailwall
	
	2. Edit brightmail.cfg in the following way:
	   In the section labeled "Symantec 3 decomposer", remove the following line:
	   blsymdec3Engine: libdec2exe.so|5
	
	3. Restart BrightMail to reload the config file: 
                  /etc/init.d/mailwall restart  
	
	For Windows:

	1. Close any open instance of the Brightmail Administration Console.
	2. Locate brightmail.cfg . 
	   The default location for this file is c:\program files\brightmail\config
	
	3. Edit brightmail.cfg in the following way:
	   In the section labeled "Symantec 3 decomposer", remove the following line:
	  blsymdec3Engine: dec2exe.dll|5
	
	4. Restart the Brightmail AntiVirus Cleaner and the Brightmail Server services.

CVE
The Common Vulnerabilities and Exposures (CVE) initiative has not yet assigned CVE Candidate CAN-2005-0249 to this issue. This is a candidate for inclusion in the CVE list (http://cve.mitre.org), which standardizes names for security problems. This section will be revised when the CVE Candidate is assigned.

Credit:
Symantec acknowledges the X-Force research team and X-Force's Alex Wheeler for identifying this issue and coordinating with Symantec to resolve and release information about the issue.

Symantec takes the security and proper functionality of our products very seriously. As founding members of the Organization for Internet Safety (OISafety), Symantec supports and follows the principles of responsible disclosure. Symantec also subscribes to the vulnerability disclosure guidelines outlined by the National Infrastructure Advisory Council (NIAC).

Please contact secure@symantec.com if you feel you have discovered a security issue in a Symantec product. A Symantec Product Security team member will contact you regarding your submission. Symantec strongly recommends using encrypted email for reporting vulnerability information to secure@symantec.com. The Symantec Product Security PGP key can be found at the end of this message.

Symantec has developed a Product Vulnerability Response document outlining the process we follow in addressing suspected vulnerabilities in our products. This document is available below.

Symantec Vulnerability Response Policy

Symantec Product Vulnerability Management PGP Key

Copyright (c) 2009 by Symantec Corp.
Permission to redistribute this alert electronically is granted as long as it is not edited in any way unless authorized by Symantec Security Response. Reprinting the whole or part of this alert in any medium other than electronically requires permission from secure@symantec.com.

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.

Symantec, Symantec products, Symantec Security Response, and secure@symantec.com are registered trademarks of Symantec Corp. and/or affiliated companies in the United States and other countries. All other registered and unregistered trademarks represented in this document are the sole property of their respective companies/owners.