iDefense Security Advisory 10.03.08 http://labs.idefense.com/intelligence/vulnerabilities/ Oct 03, 2008 I. BACKGROUND Novell eDirectory is cross platform directory server. NetWare Core Protocol, commonly referred to as NCP, is used by eDirectory to synchronize data between servers in the directory tree. NCP supports various request types, one of which is the 'Get NCP Extension Information By Name Request.' For more information, see the vendor's site found at the following link. http://www.novell.com/products/edirectory/ II. DESCRIPTION Remote exploitation of a memory corruption vulnerability in Novell Inc.'s eDirectory could allow an attacker to execute arbitrary code with the privileges of the affected service. The vulnerability exists due to an area of heap memory being used after it has already been freed. By sending malformed data it is possible to cause an area of heap memory to be freed by one thread, and then reused after another thread allocates the same area of memory. This results in the original thread operating on the data changed by the second thread, which may lead to the execution of arbitrary code. III. ANALYSIS Exploitation of this vulnerability results in the execution of arbitrary code with the privileges of the affected service, usually SYSTEM. In order to trigger this vulnerability, an attacker needs to send a series of specifically timed requests and have some degree of control of the memory layout of the process. In Labs testing, it was often difficult to reliably trigger the vulnerability. While difficult, the possibility of executing arbitrary code should not be ruled out. IV. DETECTION iDefense has confirmed the existence of this vulnerability in eDirectory version 8.8 SP2 for Windows. The Linux version does not appear to be affected. Previous versions may also be affected. V. WORKAROUND iDefense is currently unaware of any workarounds for this issue. VI. VENDOR RESPONSE Novell has released a patch for this vulnerability and advises that all users of Novell eDirectory should update. http://support.novell.com/docs/Readmes/InfoDocument/patchbuilder/readme_5037180.html http://support.novell.com/docs/Readmes/InfoDocument/patchbuilder/readme_5037181.html VII. CVE INFORMATION A Mitre Corp. Common Vulnerabilities and Exposures (CVE) number has not been assigned yet. VIII. DISCLOSURE TIMELINE 03/10/2008 Initial vendor notification 03/14/2008 Initial vendor reply 10/03/2008 Public Disclosure IX. CREDIT The discoverer of this vulnerability wishes to remain anonymous. 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@xxxxxxxxxxxx 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.