.NET Remoting allows invocation of methods across so-called remoting boundaries. Supported transports between the client and server include HTTP and TCP. .NET Remoting was already considered a legacy technology in 2009, but it is still in use due to the wide usage of ASP. NET (e.g., IIS, Sharepoint and others) and backward compatibility.
Leakage of ObjRef instances allows hackers to remotely manipulate the server, and in some cases to remotely run code on the server.
IONIX Exploit Simulation successfully simulated the leakage via a POST request to the “/RemoteApplicationMetadata.rem?wsdl” endpoint, but did not use the leaked ObjRefs to manipulate the server.
To remediate, update the ASP.NET application and verify that it does not leak ObjRef objects that could be used for attacking the server.
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