Type Confusion RCE in Microsoft Office Outlook/Word Preview Rendering

CVE-2026-47635 is a Critical remote code execution vulnerability in Microsoft Office caused by access of a resource using an incompatible type (type confusion). The available reporting indicates the flaw is in the Office document parsing/rendering pipeline used by Microsoft Word functionality and exposed through Outlook Classic, which uses Word as its rendering engine, including for the Preview Pane. A specially crafted email body, rendered message content, or malicious document/attachment can cause the Word engine to interpret attacker-controlled data as a valid object or pointer, leading to controlled memory corruption and ultimately arbitrary code execution in the context of the logged-in user. Although Microsoft’s CVSS vector lists a local attack vector, the supporting content indicates exploitation can be initiated remotely by delivering crafted content over email and triggering the vulnerable rendering path when Office processes it.