The application's list box calculate array logic keeps stale references to page or form objects after they are deleted or re-created, which allows crafted documents to trigger a use-after-free when the calculation runs and can potentially lead to arbitrary code execution.
The application does not properly validate the lifetime and validity of internal view cache pointers after JavaScript changes the document zoom and page state. When a script modifies the zoom property and then triggers a page change, the original view object may be destroyed while stale pointers are still kept and later dereferenced, which under crafted JavaScript and document structures can lead to a use-after-free condition and potentially allow arbitrary code execution.