Software Engineering Institute

Microsoft describes a named pipe as, "a specifically named one-way or two-way channel for communication between a pipe server and one or more pipe clients." Microsoft SQL Server does not correctly check named pipes. Quoting from MS03-031, "The vulnerability results because of a flaw in the checking method used by SQL Server when a client establishes an authenticated logon by using a named pipe."

A local attacker may be able to hijack a named pipe, which may result in privilege elevation. Quoting from MS03-031, "This could allow an attacker to gain control of the named pipe at the same permission level as the user attempting to connect. If the user connecting remotely had higher access rights than the attacker, the attacker could assume those rights when the named pipe was compromised."

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