3.3.1 Ensure IPv6 router advertisements are not accepted - sysctl ipv6 all accept

Information

This setting disables the system's ability to accept IPv6 router advertisements.

Rationale:

It is recommended that systems not accept router advertisements as they could be tricked into routing traffic to compromised machines. Setting hard routes within the system (usually a single default route to a trusted router) protects the system from bad routes.

Solution

Set the following parameters in /etc/sysctl.conf or a /etc/sysctl.d/* file:

net.ipv6.conf.all.accept_ra = 0
net.ipv6.conf.default.accept_ra = 0

Run the following commands to set the active kernel parameters:

# sysctl -w net.ipv6.conf.all.accept_ra=0
# sysctl -w net.ipv6.conf.default.accept_ra=0
# sysctl -w net.ipv6.route.flush=1

See Also

https://workbench.cisecurity.org/files/3738

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|SC-7(12)

Plugin: Unix

Control ID: 5d408619c75006ede0145fe0412d75e6da1d6daf901af3092d5313c5ae1a7923