From labs-no-reply@idefense.com Mon Apr 11 16:33:22 2005 From: iDEFENSE Labs To: bugtraq@securityfocus.com, vulnwatch@vulnwatch.org, full-disclosure@lists.netsys.com Date: Mon, 11 Apr 2005 15:49:12 -0400 Subject: iDEFENSE Security Advisory 04.11.05: Computer Associates BrightStor ARCserve Backup UniversalAgent Buffer Overflow Computer Associates BrightStor ARCserve Backup UniversalAgent Buffer Overflow iDEFENSE Security Advisory 04.11.05 www.idefense.com/application/poi/display?id=232&type=vulnerabilities April 11, 2005 I. BACKGROUND BrightStor ARCserve Backup provides backup and restore protection for all classes of Windows, NetWare, Linux and UNIX servers, as well as Windows, Mac OS X, Linux, UNIX, AS/400 and VMS client environments. II. DESCRIPTION Remote exploitation of a buffer overflow vulnerability in Computer Associates International Inc's BrightStor ARCserve Backup UniversalAgent may allow attackers to execute arbitrary code. The BrightStor software uses a network agent to perform backups on nodes across the network. This agent service requires either administrative credentials or a node-specific password and is capable of backing up system settings as well as files. This agent will listen on TCP and UDP ports 6050 by default. When an agent request is received on the TCP port, with the "option" field set to 0, 3 or 1000, and a large string preceding this "option" field in the packet, an overflow will occur. The agent software includes its own exception handler, preventing the service from actually crashing. Each time an exception occurs due to this overflow, the handler will kick in and restore the service back to an operating state. This particular overflow will cause three exceptions, two of which are non-exploitable, and one which can be used to hijack execution. III. ANALYSIS Successful exploitation of this vulnerability allows for a remote unauthenticated compromise with system level access. Although exploitation of this vulnerability is not trivial, it has been shown that it can be done reliably. IV. DETECTION Computer Associates BrightStor ARCserve Backup v11 (Win32) has been confirmed vulnerable. V. WORKAROUND Employ firewalls, access control lists or other TCP/UDP restriction mechanism to limit access to systems and services. VI. VENDOR RESPONSE Vendor advisories and patches for this vulnerability are available at: BrightStor ARCserve Backup r11.1 for Windows (all components): http://supportconnect.ca.com/sc/solcenter/solresults.jsp?aparno=QO66526& startsearch=1 BrightStor ARCserve Backup r11.1 Client Agent for Windows only: http://supportconnect.ca.com/sc/solcenter/solresults.jsp?aparno=QO66527& startsearch=1 BrightStor ARCserve Backup r11.1 for Windows - 64 bit edition: http://supportconnect.ca.com/sc/solcenter/solresults.jsp?aparno=QO66534& startsearch=1 BrightStor ARCserve Backup r11.0 for Windows: http://supportconnect.ca.com/sc/solcenter/solresults.jsp?aparno=QO66525& startsearch=1 BrightStor ARCserve Backup r11.0 for Windows - 64 bit edition: http://supportconnect.ca.com/sc/solcenter/solresults.jsp?aparno=QO66535& startsearch=1 BrightStor ARCserve Backup v9.01 for Windows English (all components): http://supportconnect.ca.com/sc/solcenter/solresults.jsp?aparno=QO66528& startsearch=1 BrightStor ARCserve Backup v9.01 for Windows Non-English (all components): http://supportconnect.ca.com/sc/solcenter/solresults.jsp?aparno=QO66529& startsearch=1 BrightStor ARCserve Backup v9.01 for Windows - 64 bit edition: http://supportconnect.ca.com/sc/solcenter/solresults.jsp?aparno=QO66536& startsearch=1 BrightStor ARCserve Backup v9.01 Client Agent for Windows only (English): http://supportconnect.ca.com/sc/solcenter/solresults.jsp?aparno=QO66530& startsearch=1 BrightStor ARCserve Backup v9.01 Client Agent for Windows only (Non-English): http://supportconnect.ca.com/sc/solcenter/solresults.jsp?aparno=QO66531& startsearch=1 BrightStor Enterprise Backup v10.5 for Windows: http://supportconnect.ca.com/sc/solcenter/solresults.jsp?aparno=QO66524& startsearch=1 BrightStor Enterprise Backup v10.5 for Windows - 64 bit edition: http://supportconnect.ca.com/sc/solcenter/solresults.jsp?aparno=QO66533& startsearch=1 BrightStor Enterprise Backup v10.0 for Windows: http://supportconnect.ca.com/sc/solcenter/solresults.jsp?aparno=QO66523& startsearch=1 VII. CVE INFORMATION The Common Vulnerabilities and Exposures (CVE) project has assigned the name CAN-2005-1018 to this issue. This is a candidate for inclusion in the CVE list (http://cve.mitre.org), which standardizes names for security problems. VIII. DISCLOSURE TIMELINE 12/02/2004 Initial vendor notification 12/02/2004 Initial vendor response 04/11/2005 Coordinated public disclosure IX. CREDIT The discoverer of this vulnerability wishes to remain anonymous. Get paid for vulnerability research http://www.idefense.com/poi/teams/vcp.jsp Free tools, research and upcoming events http://labs.idefense.com X. LEGAL NOTICES Copyright (c) 2005 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 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.