The Cisco router must not be configured to use IPv6 Site Local Unicast addresses.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-230041	CISC-RT-000237	SV-230041r532998_rule		Medium

Description
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.

Description

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.

STIG	Date
Cisco IOS Router RTR Security Technical Implementation Guide	2024-06-06

Details

Check Text ( C-32353r647426_chk )
Review the router configuration to ensure FEC0::/10 IPv6 addresses are not defined. If IPv6 Site Local Unicast addresses are defined, this is a finding.

Fix Text (F-32330r569546_fix)
Configure the router using only authorized IPv6 addresses.