Novell GroupWise Internet Agent RRULE Parsing: Remote Code Execution Vulnerability

Users of Novell GroupWise Internet Agent please be advised of a Remote Code Execution vulnerability that has been identified.
To view this vulnerability, possible remedies, and others please check out the Security Advisories at Critical Watch (

ZDI-10-239: [ZDI-10-239] Novell GroupWise Internet Agent RRULE Parsing Remote Code Execution Vulnerability

— Affected Products:
Novell Groupwise
— 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.

The specific flaw exists within the gwwww1.dll module responsible for
parsing VCALENDAR data within e-mail messages. When the code encounters
a RRULE variable it allocates memory for 0x800 bytes for the variable’s
contents, a list of numbers. It then proceeds to copy the numbers from
the request while there are numbers to parse. By specifying a large
amount of comma-separated values within an RRULE, an attacker can
overflow the buffer and execute arbitrary code under the context of the
SYSTEM user.