RealNetworks RealPlayer/HelixPlayer RealPix Format String Vulnerability iDEFENSE Security Advisory 09.30.05 www.idefense.com/application/poi/display?id=311&type=vulnerabilities September 30, 2005 I. BACKGROUND RealPlayer is an application for playing various media formats, developed by RealNetworks Inc. For more information, visit http://www.real.com/. II. DESCRIPTION Remote exploitation of a format string vulnerability in RealPix (.rp) file format parser within various versions of RealNetworks Inc.'s RealPlayer could allow attackers to execute arbitrary code. The vulnerability specifically exists because of the improper usage of a formatted printing function. When a user specifies an invalid value for the "timeformat" attribute describing a RealPix file, the data is passed to the function. The following stripped down .rp file is sufficient enough to trigger the vulnerability: III. ANALYSIS Exploitation allows for arbitrary code execution as the user who opened the .rp file. Exploitation requires an attacker to craft a malicious .rp file and convince a user to open it. An attacker could also trick a user to load the .rp file from a normal web page under the attacker's control; this is possible if the user has configured their web browser to handle RealPlayer formats automatically. IV. DETECTION iDEFENSE Labs has confirmed that RealPlayer 10.0.4.750 on Linux is vulnerable. Windows and Mac versions of RealPlayer are not vulnerable. FreeBSD versions are suspected vulnerable. The vendor has indicated that the following versions are vulnerable: Linux RealPlayer 10 (10.0.0 - 10.0.5) Helix Player (10.0.0 - 10.0.5) The following vendors include susceptible RealPlayer packages within their respective distributions: The FreeBSD Project: FreeBSD 5.3 and earlier Novell Inc.: SuSE Linux 9.2 Red Hat Inc.: Desktop v.3 and v.4, Enterprise Linux AS/ES/WS v.3 and v.4 and Fedora Core 3, Linux 7.3 and 9 V. WORKAROUND Filter .rp attachments at e-mail gateways. Educate users about the risks of accepting files from untrusted individuals. VI. VENDOR RESPONSE The vendor had released the following advisory for this vulnerability: http://service.real.com/help/faq/security/050930_player/EN/ VII. CVE INFORMATION The Common Vulnerabilities and Exposures (CVE) project has assigned the name CAN-2005-2710 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 08/23/2005 Initial vendor notification 09/02/2005 Initial vendor response 09/30/2005 Coordinated public disclosure IX. CREDIT iDEFENSE Labs is credited with this discovery. 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.