Symantec Security Advisory SYM05-003 08 February, 2005 Symantec UPX Parsing Engine Heap Overflow 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. 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 may 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 2/9/2004 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 Norton AntiVirus for Microsoft Exchange 2.1 build 2.18.83 Symantec Mail Security for Microsoft Exchange 4.01 build 461 Symantec Mail Security for Microsoft Exchange 4.01 build 459 Symantec Mail Security for Microsoft Exchange 4.01 build 458 Symantec Mail Security for Microsoft Exchange 4.5 build 719 Symantec AntiVirus/Filtering for Domino NT 3.1 prior to build 3.1.1 Symantec Mail Security for Domino 4.0 prior to build 4.0.1 Symantec AntiVirus/Filtering for Domino Ports 3.0 (AIX) prior to build 3.0.6 (OS400, Linux, Solaris) prior to build 3.0.7 Symantec AntiVirus Scan Engine 4.0.X all versions Symantec AntiVirus Scan Engine 4.3.X prior to build 4.3.3 Symantec AntiVirus Scan Engine for ISA 4.0.X all versions Symantec AntiVirus Scan Engine for ISA 4.3.x prior to build 4.3.3 Symantec AntiVirus Scan Engine for Netapp Filer 4.0.X all versions Symantec AntiVirus Scan Engine for Netapp Filer 4.3.X prior to build 4.3.3 Symantec AntiVirus Scan Engine for Netapp NetCache 4.0.X all versions Symantec AntiVirus Scan Engine for Netapp NetCache 4.3.X prior to build 4.3.3 Symantec AntiVirus Scan Engine for Bluecoat 4.0.X all versions Symantec AntiVirus Scan Engine for Bluecoat 4.3.X prior to build 4.3.3 Symantec AntiVirus Scan Engine for Filers 4.3.X prior to build 4.3.3 Symantec AntiVirus Scan Engine for Caching 4.3.X prior to build 4.3.3 Symantec AntiVirus for SMTP 3.1.X prior to build 3.1.7 Symantec Mail Security for SMTP 4.0 prior to build 4.0.2 Symantec Web Security 3.0 .1.X prior to build 3.0.1.70 Symantec BrightMail AntiSpam 4.0 all Symantec BrightMail AntiSpam 5.5 all Symantec AntiVirus Corporate Edition 8.1.1 build 8.1.1.314a Symantec AntiVirus Corporate Edition 8.1.1 build 8.1.1.319 Symantec AntiVirus Corporate Edition 8.1.1 build 8.1.1.323 Symantec AntiVirus Corporate Edition 8.1.1 build 8.1.1.329 Symantec AntiVirus Corporate Edition 8.01 build 8.01.434 Symantec AntiVirus Corporate Edition 8.01 build 8.01.437 Symantec AntiVirus Corporate Edition 8.01 build 8.01.446 Symantec AntiVirus Corporate Edition 8.01 build 8.01.457 Symantec AntiVirus Corporate Edition 8.01 build 8.01.460 Symantec AntiVirus Corporate Edition 8.01 build 8.01.464 Symantec AntiVirus Corporate Edition 8.01 build 8.01.471 Symantec Client Security 1.1.1 MR1 build 8.1.1.314a Symantec Client Security 1.1.1 MR2 build 8.1.1.319 Symantec Client Security 1.1.1 MR3 build 8.1.1.323 Symantec Client Security 1.1.1 MR4 build 8.1.1.329 Symantec Client Security 1.1.1 MR5 build 8.1.1.336 Symantec Client Security 1.0.1 MR3 build 8.01.434 Symantec Client Security 1.0.1 build 8.01.437 Symantec Client Security 1.0.1 MR4 build 8.01.446 Symantec Client Security 1.0.1 MR5 build 8.01.457 Symantec Client Security 1.0.1 MR6 build 8.01.460 Symantec Client Security 1.0.1 MR7 build 8.01.464 Symantec Client Security 1.0.1 MR8 build 8.01.471 Symantec Gateway Security 2.0, 2.0.1 - 5400 Series Symantec Gateway Security 1.0 - 5300 Series Consumer Products Symantec Norton Antivirus 2004 for Windows Symantec Norton Internet Security 2004 (pro) for Windows Symantec Norton System Works 2004 for Windows Symantec Norton Antivirus 8.0 for Macintosh Symantec Norton Internet Security 2.0 for Macintosh Symantec Norton System Works 7.0 for Macintosh Symantec Norton Antivirus 9.0 for Macintosh Symantec Norton Internet Security for Macintosh 3.0 Symantec Norton System Works for Macintosh 3.0 Not-Vulnerable Products (initial non-vulnerable build/Maintenance Release (MR) where indicated) Enterprise Products Norton AntiVirus for Microsoft Exchange 2.18 2.18.82 and earlier Norton AntiVirus for Microsoft Exchange 2.18 2.18.85 and later 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 Symantec AntiSpam for SMTP 3.1 Symantec AntiVirus/Filtering for Domino NT 3.1 3.1.1 Symantec Mail Security for Domino 4.0 4.0.1 Symantec Mail Security for Domino 4.1 All Symantec AntiVirus/Filtering for Domino Ports 3.0 (AIX) 3.0.6 (OS400, Linux, Solaris) 3.0.7 Symantec AntiVirus Scan Engine 4.3 4.3.3 Symantec AntiVirus Scan Engine for ISA 4.3.X 4.3.3 Symantec AntiVirus Scan Engine for Netapp Filer 4.3.X 4.3.3 Symantec AntiVirus Scan Engine for Netapp NetCache 4.3.X 4.3.3 Symantec AntiVirus for Caching 4.3.3 Symantec AntiVirus Scan Engine for Microsoft Portal Server 4.3.X Symantec AntiVirus Scan Engine for Bluecoat 4.3.X 4.3.3 Symantec AntiVirus Scan Engine for Filers 4.3.X 4.3.3 Symantec AntiVirus for Microsoft Office SharePoint Portal Server 2003 All Symantec AntiVirus for SMTP 3.1 3.1.7 Symantec Mail Security for SMTP 4.0 4.0.2 Symantec Mail Security for SMTP 4.1 Symantec Web Security 3.0 3.0.1.70 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 build 9.0.1.1.1000 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 AntiVirus for Handhelds (does not install the DEC2EXE module) 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 engineis 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 implementedin the majority of Symantec products. 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: Symantec has tested and posted hotfixes to address this issue for the affected Symantec Gateway Security 5300/5400 Series. The hotfix removes the DEC2EXE engine from the affected products and upgrades the scan engine to a new version. Product specific hotfixes are available through the Symantec Enterprise Support site http://www.symantec.com/techsupp. 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. Mitigation Symantec BrightMail AntiSpam versions 4.0 and 5.5 The DEC2EXE module can be easily and safely disabled through the brightmail.cfg file on Solaris, Linux and Windows platforms. 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 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. Credit: Symantec acknowledges the X-Force research team and X-Force's Alex Wheeler in identifying this issue and coordinating with Symantec to resolve and release information about the issue. Symantec takes the security and proper functionality of its products very seriously. As founding members of the Organization for Internet Safety (OISafety), Symantec follows the principles of responsible disclosure. Symantec also subscribes to the vulnerability guidelines outlined by the National Infrastructure Advisory Council (NIAC). Please contact secure@symantec.com if you feel you have discovered a potential or actual security issue with a Symantec product. A Symantec Product Security team member will contact you regarding your submission. Symantec has developed a Product Vulnerability Handling Process document outlining the process we follow in addressing suspected vulnerabilities in our products. We support responsible disclosure of all vulnerability information in a timely manner to protect Symantec customers and the security of the Internet as a result of vulnerability. This document is available from the location provided below. Symantec strongly recommends using encrypted email for reporting vulnerability information to secure@symantec.com. The Symantec Product Security PGP key can be obtained from the http://www.symantec.com/security page Copyright (c) 2005 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 SymSecurity are registered trademarks of Symantec Corp. and/or affiliated companies in the United States and other countries. 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