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 COMMENT variable it allocates up to 0xFFFF bytes for the variable's value. It then proceeds to copy the value into the fixed-length buffer without checking if it will fit. By specifying a large enough string in the e-mail, an attacker can overflow the buffer and execute arbitrary code under the context of the SYSTEM user.