Local Code Execution in Microsoft Office via Heap-Based Buffer Overflow

CVE-2026-45463 is a critical Microsoft Office vulnerability that can lead to code execution in the context of the affected Office application. The provided content describes the issue as a heap-based buffer overflow, and Microsoft advisory context further indicates it involves an integer underflow and buffer overflow condition in Microsoft Office. Although categorized as a remote code execution vulnerability, the available information states exploitation requires local execution context. Microsoft also notes that the Preview Pane is an attack vector, indicating that Office content rendered through Outlook/Word functionality may trigger the vulnerable condition. No specific vulnerable function or module is identified in the provided material.