__________________________________________________________ The U.S. Department of Energy Computer Incident Advisory Capability ___ __ __ _ ___ / | /_\ / \___ __|__ / \ \___ __________________________________________________________ INFORMATION BULLETIN Microsoft RPC Interface Buffer Overrun Vulnerability [Microsoft Security Bulletin MS03-026, MS03-039] July 16, 2003 21:00 GMT Number N-117 [REVISED 1 Aug 2003] [REVISED 13 Aug 2003] [REVISED 15 Aug 2003] [REVISED 22 Aug 2003] [REVISED 10 SEPT 2003] ______________________________________________________________________________ PROBLEM: A buffer overrun vulnerability exists in the part of the Windows Remote Procedure Call(RPC) that deals with message exchange over TCP/IP (Port 135). PLATFORM: Windows NT 4.0 Windows NT Server 4.0 Windows NT 4.0 Terminal Services Edition Windows 2000 Windows XP Windows Server 2003 *NOTE--If you have patched your system with MS03-026 you will need to patch your system with MS03-039. The patch provided in MS03-039 supersedes the one included in MS03-026.* If MS03-026 patches have been installed prior to the discover of the Blaster worm, your system is secure from the vulnerability that W32.Blaster is using. DAMAGE: A successful attacker would be able to run code with Local System privileges, including installing programs, changing or deleting data, or creating new accounts with full privileges. SOLUTION: Apply the respective Microsoft patches. ______________________________________________________________________________ VULNERABILITY The risk is HIGH. A successful attacker needs only to be able ASSESSMENT: to send an especially crafted packet to port 135 on the target machine. Sites that block port 135 at their incoming firewall are only vulnerable to attack by machines inside of the firewall. ______________________________________________________________________________ LINKS: CIAC BULLETIN: http://www.ciac.org/ciac/bulletins/n-117.shtml ORIGINAL BULLETINS: Released on 9/10/03 - http://www.microsoft.com/technet/treeview/default.asp? url=/technet/security/bulletin/MS03-039.asp Released on 7/16/03 - http://www.microsoft.com/technet/treeview/default.asp? url=/technet/security/bulletin/MS03-026.asp ADDITIONAL INFORMATION: 9/10/03 - For MS03-039, see CERT's Advisory: http://www.cert.org/advisories/CA-2003-23.html 7/31/03 - For MS03-026, see CERT's Advisory: http://www.cert.org/advisories/CA-2003-19.html ______________________________________________________________________________ REVISION HISTORY: 8/01/2003: Added link to CERT Advisory CA-2003-19. Contains additional information on other vulnerabilities and backdoor port activity. 8/13/2003: re-posted contents of MS bulletin to reflect revisions-to-date in the technical description workaround information, mitigating factors, and Service Pack 2 support information. 8/15/2003: Added additional information to PLATFORM section. Added Microsoft's scanner tool update information. Updated download links, removed the word "Server" from the NT4 link. 8/22/2003: Updated supercedence information in the Additional Information section. 9/10/2003: Added new bulletin from Microsoft MS03-039 which supersedes MS03-026 and updated PLATFORM section. [***** Start Microsoft Security Bulletin MS03-039 *****] Microsoft Security Bulletin MS03-039 Buffer Overrun In RPCSS Service Could Allow Code Execution (824146) Originally posted: September 10, 2003 Summary Who should read this bulletin: Users running Microsoft ® Windows ® Impact of vulnerability: Run code of attacker’s choice Maximum Severity Rating: Critical Recommendation: System administrators should apply the security patch immediately End User Bulletin: An end user version of this bulletin is available at: http://www.microsoft.com/security/security_bulletins/ms03-039.asp. Protect your PC: Additional information on how you can help protect your PC is available at the following locations: End Users can visit http://www.microsoft.com/protect IT Professionals can visit http://www.microsoft.com/technet/security/tips/ pcprotec.asp Affected Software: * Microsoft Windows NT Workstation 4.0 * Microsoft Windows NT Server® 4.0 * Microsoft Windows NT Server 4.0, Terminal Server Edition * Microsoft Windows 2000 * Microsoft Windows XP * Microsoft Windows Server 2003 Not Affected Software: * Microsoft Windows Millennium Edition Technical details Technical description: The fix provided by this patch supersedes the one included in Microsoft Security Bulletin MS03-026. Remote Procedure Call (RPC) is a protocol used by the Windows operating system. RPC provides an inter-process communication mechanism that allows a program running on one computer to seamlessly access services on another computer. The protocol itself is derived from the Open Software Foundation (OSF) RPC protocol, but with the addition of some Microsoft specific extensions. There are three identified vulnerabilities in the part of RPCSS Service that deals with RPC messages for DCOM activation— two that could allow arbitrary code execution and one that could result in a denial of service. The flaws result from incorrect handling of malformed messages. These particular vulnerabilities affect the Distributed Component Object Model (DCOM) interface within the RPCSS Service. This interface handles DCOM object activation requests that are sent from one machine to another. An attacker who successfully exploited these vulnerabilities could be able to run code with Local System privileges on an affected system, or could cause the RPCSS Service to fail. The attacker could then be able to take any action on the system, including installing programs, viewing, changing or deleting data, or creating new accounts with full privileges. To exploit these vulnerabilities, an attacker could create a program to send a malformed RPC message to a vulnerable system targeting the RPCSS Service. Microsoft has released a tool that can be used to scan a network for the presence of systems which have not had the MS03-039 patch installed. More details on this tool are available in Microsoft Knowledge Base article 827363. This tool supersedes the one provided in Microsoft Knowledge Base article 826369. If the tool provided in Microsoft Knowledge Base Article 826369 is used against a system which has installed the security patch provided with this bulletin, the superseded tool will incorrectly report that the system is missing the patch provided in MS03-026. Microsoft encourages customers to run the latest version of the tool available in Microsoft Knowledge Base article 827363 to determine if their systems are patched. Mitigating factors: * Firewall best practices and standard default firewall configurations can help protect networks from remote attacks originating outside of the enterprise perimeter. Best practices recommend blocking all ports that are not actually being used. For this reason, most systems attached to the Internet should have a minimal number of the affected ports exposed. * For more information about the ports used by RPC, visit the following Microsoft Web site: http://www.microsoft.com/technet/prodtechnol/windows2000 serv/reskit/tcpip/part4/tcpappc.asp Severity Rating: Windows NT 4.0 Server Windows NT 4.0, Terminal Server Edition Windows 2000 Windows XP Windows Server 2003 Buffer Overrun Vulnerabilities Critical Critical Critical Critical Critical Denial of Service Vulnerability None None Important None None Aggregate Severity of all Vulnerabilities Critical Critical Critical Critical Critical The above assessment is based on the types of systems affected by the vulnerability, their typical deployment patterns, and the effect that exploiting the vulnerability would have on them. Vulnerability identifier: Buffer Overrun: CAN-2003-0715 Buffer Overrun: CAN-2003-0528 Denial of Service: CAN-2003-0605 Tested Versions: Microsoft tested Windows Millennium Edition, Windows NT 4.0 Server, Windows NT 4.0 Terminal Services Edition, Windows 2000, Windows XP and Windows Server 2003 to assess whether they are affected by this vulnerability. Previous versions are no longer supported, and may or may not be affected by these vulnerabilities. Patch availability Download locations for this patch * Windows NT Workstation * Windows NT Server 4.0 * Windows NT Server 4.0, Terminal Server Edition * Windows 2000 * Windows XP * Windows XP 64 bit Edition * Windows XP 64 bit Edition Version 2003 * Windows Server 2003 * Windows Server 2003 64 bit Edition Additional information about this patch Installation platforms: * The Windows NT 4.0 patch can be installed on systems running Service Pack 6a. The Windows NT 4.0, Terminal Server Edition patch can be installed on systems running Windows NT 4.0, Terminal Server Edition Service Pack 6. * The Windows 2000 patch can be installed on systems running Windows 2000 Service Pack 2, Service Pack 3, or Service Pack 4. * The patch for Windows XP can be installed on systems running Windows XP Gold or Service Pack 1. * The patch for Windows Server 2003 can be installed on systems running Windows Server 2003 Gold. Inclusion in future service packs: The fix for this issue will be included in Windows 2000 Service Pack 5, Windows XP Service Pack 2, and Windows Server 2003 Service Pack 1. Reboot needed: Yes Patch can be uninstalled: Yes Superseded patches: The fix provided by this patch supersedes the one included in Microsoft Security Bulletin MS03-026 as well as MS01-048 Verifying patch installation: * Windows NT 4.0: To verify that the patch has been installed on the machine, confirm that all files listed in the file manifest in Knowledge Base article 824146 are present on the system. * Windows NT 4.0 Terminal Server Edition: To verify that the patch has been installed on the machine, confirm that all files listed in the file manifest in Knowledge Base article 824146 are present on the system. * Windows 2000: To verify that the patch has been installed on the machine, confirm that the following registry key has been created on the machine: HKEY_LOCAL_MACHINE\ SOFTWARE\Microsoft\Updates\Windows 2000\SP5\KB824146. To verify the individual files, use the date/time and version information provided in the file manifest in Knowledge Base article 824146 are present on the system. * Windows XP: * If installed on Windows XP Gold: To verify that the patch has been installed on the machine, confirm that the following registry key has been created on the machine: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\Windows XP\SP1\ KB824146 To verify the individual files, use the date/time and version information provided in the file manifest in Knowledge Base article 824146 are present on the system. * If installed on Windows XP Service Pack 1: To verify that the patch has been installed on the machine, confirm that the following registry key has been created on the machine: HKEY_LOCAL_MACHINE\ SOFTWARE\Microsoft\Updates\Windows XP\SP2\KB824146. To verify the individual files, use the date/time and version information provided in the file manifest in Knowledge Base article 824146 are present on the system. * Windows Server 2003: To verify that the patch has been installed on the machine, confirm that the following registry key has been created on the machine: HKEY_LOCAL_MACHINE\ SOFTWARE\Microsoft\Updates\Window Server 2003\SP1\KB824146. To verify the individual files, use the date/time and version information provided in the file manifest in Knowledge Base article 824146 are present on the system. Caveats: None Localization: Localized versions of this patch are available at the locations discussed in “Patch Availability”. Obtaining other security patches: Patches for other security issues are available from the following locations: * Security patches are available from the Microsoft Download Center, and can be most easily found by doing a keyword search for "security_patch". * Patches for consumer platforms are available from the Windows Update web site Other information: Acknowledgments Microsoft thanks eEye Digital Security, NSFOCUS Security Team, and Xue Yong Zhi and Renaud Deraison from Tenable Network Security for reporting the buffer overrun vulnerabilities and working with us to protect customers. Support: * Microsoft Knowledge Base article 824146 discusses this issue and will be available approximately 24 hours after the release of this bulletin. Knowledge Base articles can be found on the Microsoft Online Support web site. * Technical support is available from Microsoft Product Support Services. There is no charge for support calls associated with security patches. Security Resources: The Microsoft TechNet Security Web Site provides additional information about security in Microsoft products. Disclaimer: The information provided in the Microsoft Knowledge Base is provided "as is" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply. Revisions: V1.0 September 10, 2003: Bulletin Created. [***** End Microsoft Security Bulletin MS03-039 *****] _______________________________________________________________________________ CIAC wishes to acknowledge the contributions of Microsoft Corporation for the information contained in this bulletin. _______________________________________________________________________________ CIAC, the Computer Incident Advisory Capability, is the computer security incident response team for the U.S. Department of Energy (DOE) and the emergency backup response team for the National Institutes of Health (NIH). CIAC is located at the Lawrence Livermore National Laboratory in Livermore, California. CIAC is also a founding member of FIRST, the Forum of Incident Response and Security Teams, a global organization established to foster cooperation and coordination among computer security teams worldwide. CIAC services are available to DOE, DOE contractors, and the NIH. CIAC can be contacted at: Voice: +1 925-422-8193 (7x24) FAX: +1 925-423-8002 STU-III: +1 925-423-2604 E-mail: ciac@ciac.org Previous CIAC notices, anti-virus software, and other information are available from the CIAC Computer Security Archive. World Wide Web: http://www.ciac.org/ Anonymous FTP: ftp.ciac.org PLEASE NOTE: Many users outside of the DOE, ESnet, and NIH computing communities receive CIAC bulletins. If you are not part of these communities, please contact your agency's response team to report incidents. Your agency's team will coordinate with CIAC. The Forum of Incident Response and Security Teams (FIRST) is a world-wide organization. A list of FIRST member organizations and their constituencies can be obtained via WWW at http://www.first.org/. This document was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor the University of California nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial products, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation or favoring by the United States Government or the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or the University of California, and shall not be used for advertising or product endorsement purposes. 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