iDefense Security Advisory 09.26.11 http://labs.idefense.com/intelligence/vulnerabilities/ Sep 26, 2011 I. BACKGROUND GroupWise is Novell's messaging platform, and includes support for email, calendaring, and instant messaging. More information is available at the following website: http://www.novell.com/products/groupwise/ II. DESCRIPTION Remote exploitation of a memory corruption vulnerability in Novell Inc.'s GroupWise could allow an attacker to execute arbitrary code with the privileges of the affected service. This vulnerability is present in the calendar processing code, which resides within the GroupWise Internet Agent (GWIA) process. The vulnerability occurs when parsing a malformed calendar recurrence (RRULE) that recurs weekly. Specifically, by using a negative integer for the BYWEEKNO property, it is possible to trigger a write operation beyond the bounds of an allocated heap buffer. This can lead to the corruption of memory, and 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. On Windows, the GWIA process runs with SYSTEM privileges. In order to exploit this vulnerability, an attacker simply needs to send an email to a valid user, and attach the malicious calendar file to the email. The targeted user does not need to download or view the email; processing of the iCal file occurs automatically on the server as soon as the email is received by the server. IV. DETECTION Novell GroupWise 8.0x up to (and including) 8.02HP2 are vulnerable. V. WORKAROUND iDefense is currently unaware of any workaround for this issue. VI. VENDOR RESPONSE Novell has released fixes which addresses this issue. Information about downloadable vendor updates can be found by clicking on the URLs shown. http://www.novell.com/support/search.do?cmd=displayKC&docType=kc&externalId=7009215&sliceId=1&docTypeID=DT_TID_1_1&dialogID=269235469&stateId=0%200%20269237764 VII. CVE INFORMATION The Common Vulnerabilities and Exposures (CVE) project has assigned the name CVE-2011-2662 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 07/20/2011 Initial Vendor Notification 07/21/2011 Vendor Reply 09/26/2011 Coordinated 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 © 2011 Verisign 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.