A vulnerability in the Windows Remote Procedure Call (RPC) mechanism allows attackers to elevate their privileges to System, Kaspersky reports. The local privilege escalation issue potentially affects all Windows versions and abuses another legitimate Windows mechanism, where processes are allowed to impersonate other processes to perform specific actions. The root cause of the security defect, which Kaspersky researcher Haidar Kabibo named PhantomRPC, is an architectural weakness, potentially turning any process that depends on RPC into a possible escalation path. In Windows, RPC is the mechanism that allows processes to communicate with one another and invoke functions that are implemented in other processes, regardless of their execution contexts. It uses a client–server model, where…