Windows Exploitation Techniques: Dangling COM Object Registrations

Microsoft has fixed CVE-2026-66804, a Windows privilege-escalation flaw involving a dangling registration for the CrossDevice COM object. The issue, an incomplete remediation for CVE-2026-50343, could let a local user place a DLL in a writable ProgramData path and have it loaded by a privileged COM service. Google Project Zero shows how custom COM marshaling and the Shell Create Object Handler could be used to reach SYSTEM-level code execution.