The system must disable TCP reverse IP source routing.

If enabled, reverse IP source routing would allow an attacker to more easily complete a three-way TCP handshake and spoof new connections.

Determine if TCP reverse IP source routing is disabled.

# ipadm show-prop -p _rev_src_routes -co current tcp

If the output of this command is not "0", this is a finding.

The Network Management profile is required.

Disable reverse source routing.

# pfexec ipadm set-prop -p _rev_src_routes=0 tcp