Tunnel entry and exit points must be in a deny-by-default security posture.

From Perimeter L3 Switch Security Technical Implementation Guide - Cisco

Associated with IA controls: ECSC-1

SV-20240r2_rule Tunnel entry and exit points must be in a deny-by-default security posture.

Vulnerability discussion

Having tunnels in a permit any any posture allow traffic to enter and exit the enclave without control from the Information Assurance team or SA.

Check content

Follow the procedures defined in NET-TUNL-002 to determine all tunnel entry and exit points, then ensure each end-point is in a deny by default posture inbound and outbound.

Fix text

Apply a deny by default posture on every tunnel end-point.

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