Title

The router must not be configured to use IPv6 Site Local Unicast addresses. (Cat II impact)

Discussion

As currently defined, site local addresses are ambiguous and can be present in multiple sites. The address itself does not contain any indication of the site to which it belongs. The use of site-local addresses has the potential to adversely affect network security through leaks, ambiguity, and potential misrouting as documented in section 2 of RFC3879. RFC3879 formally deprecates the IPv6 site-local unicast prefix FEC0::/10 as defined in RFC3513.

Check Content

Review the router configuration to ensure FEC0::/10 IP addresses are not defined. If IPv6 Site Local Unicast addresses are defined, this is a finding.

Fix Text

Configure the router using authorized IPv6 addresses.

Additional Identifiers

Rule ID: SV-220145r604135_rule

Vulnerability ID: V-220145

Group Title: SRG-NET-000512

Expert Comments

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