A maliciously crafted DWFX file, when parsed in w3dtk.dll through Autodesk Navisworks, can force a Heap-based Buffer Overflow. A malicious actor can leverage this vulnerability to cause a crash or execute arbitrary code in the context of the current process.
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
The product writes data past the end, or before the beginning, of the intended buffer.