__________________________________________________________ The U.S. Department of Energy Computer Incident Advisory Capability ___ __ __ _ ___ / | /_\ / \___ __|__ / \ \___ __________________________________________________________ INFORMATION BULLETIN Microsoft Network DDE Agent Request Vulnerability February 9, 2001 23:00 GMT Number L-044 ______________________________________________________________________________ PROBLEM: A flaw in the Network Dynamic Data Exchange (DDE) agent could enable unprivileged users to run code and elevate privileges on a local machine. PLATFORM: Windows 2000 only. (does not affect NT). DAMAGE: Elevation of privileges could result in a Administrator compromise. Note the user must have a legitimate account on the system to exploit this vulnerability. SOLUTION: Apply patches described in this bulletin. Also, Win 2000 servers should be configured such that unprivileged users do not have execute privileges on local server. ______________________________________________________________________________ VULNERABILITY LOW. This cannot be exploited remotely, and the user must have ASSESSMENT: access to the local machine, and have an account for a successful elevation of privileges. ______________________________________________________________________________ [****** Start Microsoft Advisory ******] -----BEGIN PGP SIGNED MESSAGE----- - ---------------------------------------------------------------------- Title: Patch Available for "Network DDE Agent Request" Vulnerability Date: 05 February 2001 Software: Windows 2000 Impact: Privilege elevation Bulletin: MS01-007 Microsoft encourages customers to review the Security Bulletin at: http://www.microsoft.com/technet/security/bulletin/MS01-007.asp. - ---------------------------------------------------------------------- Issue: ====== Network Dynamic Data Exchange (DDE) is a technology that enables applications on different Windows computers to dynamically share data. This sharing is effected via communications channels called trusted shares, which are managed by a service called the Network DDE Agent. By design, processes on the local machine can levy requests upon the Network DDE Agent, including ones that indicate what application should be run in conjunction with a particular trusted share. However, a vulnerability exists because, in Windows 2000, the Network DDE Agent runs using the Local System security context and processes all requests using this context, rather than that of the user. This would give an attacker an opportunity to cause the Network DDE Agent to run code of her choice in Local System context, as a means of gaining complete control over the local machine. Microsoft recommends that customers using Windows 2000 workstations or who allow unprivileged users to run code on Windows 2000 servers apply the patch immediately. In addition, customers operating Windows 2000 web servers should consider applying the patch to those machines as well, as a precautionary measure. If an attacker were able to gain the ability to run code in a restricted context on a web server via another vulnerability, this vulnerability would provide a way to immediately elevate her privileges and cause broader damage. Mitigating Factors: ==================== - The vulnerability would not affect terminal servers unless the attacker could log on at the console. Best practices recommend against this. - Servers could only be affected if the attacker were given the ability to load a program of her choice onto the machine and execute it locally. Best practices recommend against this. - Workstations, the machines primarily at risk, typically would not provide a way for the attacker to use control over the local machine to gain domain-wide privileges Patch Availability: =================== - A patch is available to fix this vulnerability. Please read the Security Bulletin http://www.microsoft.com/technet/security/bulletin/ms01-007.asp for information on obtaining this patch. Acknowledgment: =============== - Dildog of @Stake (http://www.atstake.com) - --------------------------------------------------------------------- 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. -----BEGIN PGP SIGNATURE----- Version: PGP Personal Privacy 6.5.3 iQEVAwUBOn8m640ZSRQxA/UrAQHqOwgAr2o3EcqEHjXMHKngVUsEcUeTcCI9NtP4 CsfJjsVtDO2Ll9iGU9G/z9zNZZmTfMkNQbWi1two3Phu21fdSgkvBCNUgWQziwcA 5Iuzn4dZEBC/tJXrQxqEfyYrx1GeZVN585aBuxTLsno2buEyGeHU7DTvvZ8/4KYg iNz55fotYf60NqQzCw8NNJMelcKn4t0sVvMOrty0jbZ5MflySgRaw7F+gqzRJ0Ox 2NKIrU1xkNKnmabeE7kFKiOfImV6D5blBbqwHAQfeicAKC4P3b1lfixbdivSE6Ih TTnJEs+D3EX+irAWCSB8RUvSa1eY7zyRx2JwglPZhckXGwGgLHQkjQ== =lgJl -----END PGP SIGNATURE----- [****** End Microsoft Advisory ******] _______________________________________________________________________________ CIAC wishes to acknowledge the contributions of Microsoft 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/ (or http://ciac.llnl.gov -- they're the same machine) Anonymous FTP: ftp.ciac.org (or ciac.llnl.gov -- they're the same machine) 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. LAST 10 CIAC BULLETINS ISSUED (Previous bulletins available from CIAC) L-034: HP Security Vulnerability in man(1) Command L-035: HP-UX Support Tools Manager Vulnerability L-036: FreeBSD procfs Vulnerabilities L-037: FreeBSD periodic Uses Insecure Temporary Files L-038: FreeBSD inetd ident Server Vulnerability L-039: FreeBSD sort Uses Insecure Temporary Files L-040: The Ramen Worm L-041: Microsoft Hotfix Packaging Anomalies L-042: Compaq Web-enabled Management Software Buffer Overflow L-043: Microsoft NTLMSSP Privilege Elevation Vulnerability