Title

SLEM 5 must not be performing Internet Protocol version 6 (IPv6) packet forwarding by default unless the system is a router. (Cat II impact)

Discussion

Routing protocol daemons are typically used on routers to exchange network topology information with other routers. If this software is used when not required, system network information may be unnecessarily transmitted across the network.

Check Content

Verify SLEM 5 is not performing IPv6 packet forwarding by default, unless the system is a router with the following command: > sudo sysctl net.ipv6.conf.default.forwarding net.ipv6.conf.default.forwarding = 0 If the network parameter "ipv6.conf.default.forwarding" is not equal to "0", or nothing is returned, this is a finding.

Fix Text

Configure SLEM 5 to not performing IPv6 packet forwarding by default by running the following command as an administrator: > sudo sysctl -w net.ipv6.conf.default.forwarding=0 If "0" is not the system's default value, add or update the following line in "/etc/sysctl.d/99-stig.conf": > sudo sh -c 'echo "net.ipv6.conf.default.forwarding=0" >> /etc/sysctl.d/99-stig.conf' > sudo sysctl --system

Additional Identifiers

Rule ID: SV-261326r996448_rule

Vulnerability ID: V-261326

Group Title: SRG-OS-000480-GPOS-00227

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.