===================================================================== CERT-Renater Note d'Information No. 2005/VULN201 _____________________________________________________________________ DATE : 18/03/2005 HARDWARE PLATFORM(S) : / OPERATING SYSTEM(S) : Systems running McAfee AntiVirus Library versions prior to 4400. ====================================================================== Internet Security Systems Protection Advisory March 17, 2005 McAfee AntiVirus Library Stack Overflow Summary: ISS has shipped protection for a flaw X-Force has discovered in McAfee AntiVirus Library versions prior to 4400. The McAfee AntiVirus Library is widely relied upon to provide antivirus capabilities to desktop, server, and gateway systems. Also, several large vendors and ISP's implement McAfee's AntiVirus Library in their products. By crafting an LHA file, an attacker is able to trigger a stack overflow within the process importing the McAfee AntiVirus Library. ISS Protection Strategy: ISS has provided preemptive protection for these vulnerabilities. We recommend that all customers apply applicable ISS product updates. Network Sensor 7.0, Proventia A and G100, G200, G1200: XPU 24.3 / 3/14/05 LHA_File_Path_Overflow Proventia M and G400, G2000: XPU 1.42 / 3/14/05 LHA_File_Path_Overflow Server Sensor 7.0: XPU 24.3 / 3/14/05 LHA_File_Path_Overflow Desktop Protector 7.0: Version EOB / 3/14/05 LHA_File_Path_Overflow BlackICE Agent for Server 3.6: Version EOB / 3/14/05 LHA_File_Path_Overflow These updates are now available from the ISS Download Center at: http://www.iss.net/download. Business Impact: Compromise of antivirus protected networks and machines may lead to exposure of confidential information, loss of productivity, and further network compromise. Successful exploitation of this vulnerability could be used to gain unauthorized access to networks and machines being protected by McAfee AntiVirus Library product. Implementations of McAfee AntiVirus Library are likely vulnerable through common protocols, e.g. SMTP, HTTP, FTP, SMB. No authentication is required for an attacker to leverage this vulnerability to compromise a antivirus protected network or machine. It is likely McAfee AntiVirus Library implementations are vulnerable in their default configurations. Affected Products: Active Virus Defense Active VirusScan Active Virus Defense SMB Edition Active VirusScan SMB Edition Active Threat Protection Active Mail Protection GroupShield for Exchange GroupShield for Exchange 5.5 GroupShield for Lotus Domino GroupShield for Mail Servers with ePO LinuxShield NetShield for Netware PortalShield for Microsoft SharePoint SecurityShield for Microsoft ISA Server Virex VirusScan (all versions) VirusScan Professional VirusScan ASaP/Managed VirusScan VirusScan Command Line VirusScan for NetApp VirusScan(r) Enterprise(all versions) WebShield Appliances WebShield SMTP Note: Additional versions may be affected, please contact your vendor for confirmation. In addition, several ISPs and vendors also use McAfee AntiVirus Library and are likely vulnerable. Description: McAfee Antivirus Library is used to parse different file formats to detect malware. One of the modules in McAfee Antivirus Library parses the LHA file format. Before LHA decompression, the library does not properly check the length of type 2 header file name fields. The LHA engine ensures the header field is no longer than 0x167 bytes, but has only allocated 0x130 bytes of stack space when the copy takes place. In order to trigger the overflow, the LHA file must be malformed, and conform to another non-archive file format. By sending this malformed and dual format file, an attacker can execute arbitrary code in SYSTEM context across platforms in a reliable manner. This vulnerability can be triggered by an unauthenticated remote attacker, without user interaction, by sending an e-mail containing a crafted LHA file to the target McAfee AntiVirus Library on client, server, and gateway implementations. Additional attack vectors exist over other common protocols (e.g. HTTP, FTP, POP3, SMB), but some may require user interaction. The ISS X-Press Updates detailed above have the ability to protect against attack attempts targeted at McAfee products. Credit: This vulnerability was discovered and researched by Alex Wheeler of ISS X-Force. ______ About Internet Security Systems (ISS) Internet Security Systems, Inc. (ISS) is the trusted security expert to global enterprises and world governments, providing products and services that protect against Internet threats. An established world leader in security since 1994, ISS delivers proven cost efficiencies and reduces regulatory and business risk across the enterprise for more than 11,000 customers worldwide. ISS products and services are based on the proactive security intelligence conducted by ISS’ X-Force® research and development team – the unequivocal world authority in vulnerability and threat research. Headquartered in Atlanta, Internet Security Systems has additional operations throughout the Americas, Asia, Australia, Europe and the Middle East. Copyright (c) 2005 Internet Security Systems, Inc. All rights reserved worldwide. This document is not to be edited or altered in any way without the express written consent of Internet Security Systems, Inc. If you wish to reprint the whole or any part of this document, please email xforce@iss.net for permission. You may provide links to this document from your web site, and you may make copies of this document in accordance with the fair use doctrine of the U.S. copyright laws. Disclaimer: The information within this document may change without notice. Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. In no event shall the author/distributor (Internet Security Systems X-Force) be held liable for any damages whatsoever arising out of or in connection with the use or spread of this information. X-Force PGP Key available on MIT's PGP key server and PGP.com's key server, as well as at http://www.iss.net/security_center/sensitive.php Please send suggestions, updates, and comments to: X-Force xforce@iss.net of Internet Security Systems, Inc. ====================================================================== ========================================================= Les serveurs de référence du CERT-Renater http://www.urec.fr/securite http://www.cru.fr/securite http://www.renater.fr ========================================================= + CERT-RENATER | tel : 01-53-94-20-44 + + 151 bd de l'Hopital | fax : 01-53-94-20-41 + + 75013 Paris | email: certsvp@renater.fr + =========================================================