__________________________________________________________ The U.S. Department of Energy Computer Incident Advisory Capability ___ __ __ _ ___ / | /_\ / \___ __|__ / \ \___ __________________________________________________________ INFORMATION BULLETIN Trillian Instant Messenger Client Vulnerability [US-CERT Vulnerability Note VU#786920] July 17, 2007 18:00 GMT Number R-306 ______________________________________________________________________________ PROBLEM: The Trillian Instant Messenger client contains a buffer overflow vulnerability that may allow an attacker to execute code. PLATFORM: Trillian Instant Messenger Client DAMAGE: May allow an attacker to execute code. SOLUTION: There is no practical solution to this problem at this time. See bulletin for workarounds. ______________________________________________________________________________ VULNERABILITY The risk is LOW. May allow an attacker to execute code. ASSESSMENT: ______________________________________________________________________________ LINKS: CIAC BULLETIN: http://www.ciac.org/ciac/bulletins/r-306.shtml ORIGINAL BULLETIN: http://www.kb.cert.org/vuls/id/786920 ______________________________________________________________________________ [***** Start US-CERT Vulnerability Note VU#786920 *****] Vulnerability Note VU#786920 Trillian Instant Messenger client fails to properly handle malformed URIs Overview The Trillian Instant Messaging client contains a buffer overflow vulnerability that may allow an attacker to execute code. I. Description A Uniform Resource Identifier (URI) is a string of characters that can be used to identify a location, resource, or protocol. The Trillian Instant Messenger client is an IM application that supports multiple services, including AOL Instant Messenger. Trillian registers itself as the default handler for aim: URIs during installation. Web browsers may pass URIs to other applications that have been registered to handle them. A buffer overflow vulnerability exists in the Trillian Instant Messenger client. An attacker may exploit this vulnerability by convincing a user to open a malformed aim: URI inside of a web browser. When the web browser passes the malformed URI to the Trillian Instant Messenger client, the overflow may be triggered. Note that some web browsers may present a dialog box warning that the aim: URI is being handed off to another program. II. Impact A remote, unauthenticated attacker may be able to execute arbitrary code with the privileges of the user running Trillian. III. Solution We are currently unaware of a practical solution to this problem. Unregister the AIM protocols Disabling the AIM protocol handler will mitigate this vulnerability. To unregister the protocol handlers, delete or rename the following registry keys: HKEY_CLASSES_ROOT\AOL Block access to aim: URIs Administrators may partially mitigate this vulnerability by blocking access to the aim: URI using proxy server access control lists or the appropriate content filtering rule. Systems Affected Vendor Status Date Updated America Online, Inc. Not Vulnerable 16-Jul-2007 Cerulean Studios Vulnerable 16-Jul-2007 References http://www.xs-sniper.com/nmcfeters/Cross-App-Scripting-2.html http://en.wikipedia.org/wiki/Uniform_Resource_Identifier Credit This issue was disclosed by Nate Mcfeters, Billy (BK) Rios, Raghav "the Pope" Dube. This document was written by Ryan Giobbi. Other Information Date Public 07/15/2007 Date First Published 07/16/2007 04:40:45 PM Date Last Updated 07/16/2007 CERT Advisory CVE Name Metric 23.76 Document Revision 10 [***** End US-CERT Vulnerability Note VU#786920 *****] _______________________________________________________________________________ CIAC wishes to acknowledge the contributions of US-CERT 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. LAST 10 CIAC BULLETINS ISSUED (Previous bulletins available from CIAC) R-296: Vulnerability in Microsoft Internet Information Services (939373) R-297: Vulnerabilities in Microsoft Excel (936542) R-298: Vulnerability in Windows Vista Firewall (935807) R-299: Vulnerability in Microsoft Office Publisher 2007 (936548) R-300: Flash Player Vulnerability R-301: Security Vulnerability in the rcp(1) Command R-302: Security Vulnerability inJava Web Start URL Parsing Code R-303: VideoLan Vulnerability R-304: Java Runtime Environment Vulnerability R-305: Tomcat Security Update