TippingPoint Zero Day Initiative

Novell Groupwise iCal COMMENT, RRULE, TZNAME Remote Code Execution Vulnerabilities

ZDI-11-285: October 13th, 2011


CVSS Score

Affected Vendors

Affected Products


TippingPoint™ IPS Customer Protection

TippingPoint IPS customers are protected against this vulnerability by Digital Vaccine protection filter ID 10650,10651,10655. For further product information on the TippingPoint IPS:

Vulnerability Details

This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Novell GroupWise. Authentication is not required to exploit this vulnerability.

Multiple flaws exist within the gwwww1.dll module responsible for parsing VCALENDAR data within e-mail messages. When encountering a RRULE, COMMENT, or TZNAME parameter a static sized memory buffer is allocated. Insufficient checks are performed to ensure the size of the parameter's value can be contained in this buffer. An attacker can overflow the buffer and execute arbitrary code under the context of the SYSTEM user.

Vendor Response

Novell has issued an update to correct this vulnerability. More details can be found at:

Disclosure Timeline

    2011-04-01 - Vulnerability reported to vendor
    2011-10-13 - Coordinated public release of advisory


This vulnerability was discovered by: