iDefense Security Advisory 07.31.08 http://labs.idefense.com/intelligence/vulnerabilities/ Jul 31, 2008 I. BACKGROUND Mac OS X is a Unix operating system built from the XNU kernel. Mac OS X provides all the standard Unix capabilities and tools with an additional GUI component. For more information, see the vendor's site found at the following link URL. http://www.apple.com/macosx/ II. DESCRIPTION Remote exploitation of an integer overflow vulnerability in Apple Inc.'s Mac OS X could allow an attacker to execute arbitrary code with the privileges of the currently logged in user. This vulnerability exists due to the way PDF files containing Type 1 fonts are handled. When processing a font with an overly large length, integer overflow could occur. This issue leads to heap corruption which can allow for arbitrary code execution. III. ANALYSIS Exploitation of this issue allows an attacker to execute arbitrary code. An attacker could exploit this issue via multiple attack vectors. The most appealing vector for attack is Safari. An attacker could host a malformed PDF file on a website and entice a targeted user to open a URL. Upon opening the URL in Safari the PDF file will be automatically parsed and exploitation will occur. While this is the most appealing attack vector, the file can also be attached to an e-mail. Any application which uses the Apple libraries for file open dialogs will crash upon previewing the malformed PDF document. IV. DETECTION iDefense has confirmed the existence of this vulnerability in Mac OS X version 10.5.2. Previous versions may also be affected. V. WORKAROUND iDefense is currently unaware of any workarounds for this issue. VI. VENDOR RESPONSE Apple addressed this vulnerability within their Mac OS X 2008-005 security update. More information is available at the following URL. http://support.apple.com/kb/HT2647 VII. CVE INFORMATION The Common Vulnerabilities and Exposures (CVE) project has assigned the name CVE-2008-2322 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 07/09/2008 Initial vendor notification 07/10/2008 Initial vendor response 07/31/2008 Public disclosure IX. CREDIT This vulnerability was reported to iDefense by Pariente Kobi. Get paid for vulnerability research http://labs.idefense.com/methodology/vulnerability/vcp.php Free tools, research and upcoming events http://labs.idefense.com/ X. LEGAL NOTICES Copyright © 2008 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 e-mail 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.