__________________________________________________________ The U.S. Department of Energy Computer Incident Advisory Capability ___ __ __ _ ___ / | /_\ / \___ __|__ / \ \___ __________________________________________________________ INFORMATION BULLETIN Microsoft V1 Exchange Server Security Certificates Vulnerability [Microsoft Security Bulletin MS03-003] January 23, 2003 20:00 GMT Number N-035 ______________________________________________________________________________ PROBLEM: A V1 Exchange Server Security certificate is one of the encryption certificate options that is available when Outlook 2002 is used in conjunction with a Microsoft Exchange mail server. There is a flaw in the way Outlook 2002 handles a V1 Exchange Server Security certificate. AFFECTED Microsoft Content Management Server 2001/Exchange using V1 SOFTWARE: Exchange Server Security Certificates DAMAGE: As a result of this flaw, Outlook fails to encrypt the mail correctly and the message will be sent in plain text. This could cause the information in the e-mail to be exposed when the user believed it to be protected through encryption. SOLUTION: Apply available patch. ______________________________________________________________________________ VULNERABILITY The risk is LOW. The Exchange mail server's default certificate ASSESSMENT: type is an S/MIME certificate - not a V1 Exchange Server Security certificate. This vulnerability only affects Outlook 2002 and only when sending HTML e-mail. ______________________________________________________________________________ LINKS: CIAC BULLETIN: http://www.ciac.org/ciac/bulletins/n-035.shtml ORIGINAL BULLETIN: http://www.microsoft.com/technet/treeview/default.asp?url= /technet/security/bulletin/MS03-003.asp ______________________________________________________________________________ [***** Start Microsoft Security Bulletin MS03-003 *****] Microsoft Security Bulletin MS03-003 Flaw in how Outlook 2002 handles V1 Exchange Server Security Certificates could lead to Information Disclosure (812262) Originally posted: January 22, 2003 Summary Who should read this bulletin: Administrators of Microsoft Outlook 2002 systems using V1 Exchange Server Security certificates for encryption. Impact of vulnerability: Information Disclosure Maximum Severity Rating: Moderate Recommendation: Administrators of Microsoft Outlook 2002 systems using V1 Exchange Server Security certificates for encryption should apply the patch immediately. Affected Software: Microsoft Outlook 2002 End User Bulletin: An end user version of this bulletin is available at: http://www.microsoft.com/security/security_bulletins/ms03-003.asp. Technical details Technical description: Microsoft Outlook 2002 provides the facility to encrypt e-mails sent between e-mail recipients. Encryption is used to prevent parties other than the intended recipients from reading the contents of an e-mail. Outlook uses public key certificates to facilitate the exchange of the cryptographic keys that are used in the encryption process, and Outlook offers a number of different options as to what type of certificates can be used. S/MIME certificates are the most commonly used (and are not affected by the vulnerability that is the subject of this bulletin), but there are other certificate options including V1 Exchange Server Security certificates. A vulnerability exists because there is a flaw in the way Outlook 2002 handles a V1 Exchange Server Security certificate when using it to encrypt e-mail. As a result of this flaw, Outlook fails to encrypt the mail correctly and the message will be sent in plain text. This could cause the information in the e-mail to be exposed when the user believed it to be protected through encryption. Mitigating factors: This vulnerability only affects encryption when a V1 Exchange Server Security certificate is used. S/MIME encryption, which is the most widely used form of e-mail encryption used by Outlook, is not affected. This vulnerability only affects Outlook 2002 and only when sending HTML e-mail. Severity Rating: Outlook 2002 Moderate 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: CAN-2003-0007 Tested Versions: Microsoft tested Outlook 98, Outlook 2000 and Outlook 2002 to assess whether they are affected by these vulnerabilities. Previous versions are no longer supported, and may or may not be affected by these vulnerabilities. Patch availability Download locations for this patch Microsoft Outlook 2002: http://microsoft.com/downloads/details.aspx? FamilyId=F20A2E4B-E458-48F0-B0CB-7E73C0BB4884&displaylang=en http://www.microsoft.com/office/ork/xp/journ/olk1006a.htm (administrative update only) Note: This and other Office updates can be obtained at http://office.microsoft.com/productupdates. Additional information about this patch Installation platforms: This patch can be installed on systems running Outlook 2002 with Office XP Service Pack 2. (The administrative update can be installed on systems running Office XP Service Pack 1 as well). Inclusion in future service packs: The fix for this issue will be included in any future service packs for Office XP. Reboot needed: No Patch can be uninstalled: No Superseded patches: None. Verifying patch installation: Start Microsoft Outlook, and then click About Microsoft Outlook on the Help menu. The product version is 10.4712.4219 if the patch is installed. 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 WindowsUpdate web site Other information: Support: Microsoft Knowledge Base article 812262 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 January 22, 2003: Bulletin Created. [***** End Microsoft Security Bulletin MS03-003 *****] _______________________________________________________________________________ CIAC wishes to acknowledge the contributions of Microsoft Corportaion 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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