This vulnerability allows remote attackers to potentially execute arbitrary code on vulnerable installations of Cerulean Studios Trillian. Authentication is not required to exploit this vulnerability.
The specific flaw exists within the XML processing code for Trillian. When parsing specially formulated xml, the application will corrupt an internal data structure. Whilst deallocating this data structure, the application can be tricked into freeing a single allocated chunk multiple times, which can potentially lead to code execution.