remoteDCOM

remoteDCOM refers to the capability of the Distributed Component Object Model (DCOM) to perform remote procedure calls and manage COM objects on remote computers over a network. DCOM is an extension of the Component Object Model (COM) that enables software components to communicate across process and machine boundaries, allowing a client to create and interact with objects hosted on a distant server as if they were local.

How it works in practice involves several elements. A client uses COM interfaces to request a remote object, which is activated on the target machine through the DCOM infrastructure. Communication is carried over the Remote Procedure Call (RPC) protocol, with an RPC Endpoint Mapper service helping to locate the correct port and interface on the remote host. DCOM security combines authentication, authorization, and access control to govern remote interactions, and configuration can be adjusted via administration tools such as DCOMCNFG and Component Services.

In security contexts, remoteDCOM has historically represented an exposed surface when DCOM/RPC endpoints are reachable across networks. The architecture relies on ports that can be scanned or abused if not properly restricted, with the commonly cited requirement to manage exposure of RPC endpoint mapper on port 135 and the many dynamically assigned ports used thereafter. Organizations often mitigate risk by disabling DCOM where remote access is unnecessary, restricting RPC exposure with firewalls, applying security patches, and enforcing principle of least privilege on remote object activations.

Overall, remoteDCOM remains a foundational capability within Windows interprocess and intermachine communication, balanced by careful security governance and network hardening.