cyberstrikeus 7.3.1 Disable IPv6 Router Advertisements (Not Scored)
Profile Applicability
- Level 1
Description
This setting disables the systems ability to accept 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.
Audit Procedure
Using Command Line
Perform the following to determine if the system is disabled from accepting router advertisements:
/sbin/sysctl net.ipv6.conf.all.accept_ra
/sbin/sysctl net.ipv6.conf.default.accept_ra
Expected Result
net.ipv6.conf.all.accept_ra = 0
net.ipv6.conf.default.accept_ra = 0
Remediation
Using Command Line
Set the net.ipv6.conf.all.accept_ra and net.ipv6.conf.default.accept_ra parameter to 0 in /etc/sysctl.conf:
net.ipv6.conf.all.accept_ra=0
net.ipv6.conf.default.accept_ra=0
Modify active kernel parameters to match:
/sbin/sysctl -w net.ipv6.conf.all.accept_ra=0
/sbin/sysctl -w net.ipv6.conf.default.accept_ra=0
/sbin/sysctl -w net.ipv6.route.flush=1
Default Value
IPv6 router advertisements are accepted by default.
References
- CIS Ubuntu 12.04 LTS Server Benchmark v1.1.0
Profile
Level 1 - Not Scored