3.6.3 Ensure loopback traffic is configured - output

Information

Configure the loopback interface to accept traffic. Configure all other interfaces to deny traffic to the loopback network (127.0.0.0/8). Loopback traffic is generated between processes on machine and is typically critical to operation of the system. The loopback interface is the only place that loopback network (127.0.0.0/8) traffic should be seen, all other interfaces should ignore traffic on this network as an anti-spoofing measure.

Solution

Run the following commands to implement the loopback rules: # iptables -A INPUT -i lo -j ACCEPT# iptables -A OUTPUT -o lo -j ACCEPT# iptables -A INPUT -s 127.0.0.0/8 -j DROP

See Also

https://workbench.cisecurity.org/files/1866

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|SC-7(12), CSCv6|9.2

Plugin: Unix

Control ID: f0e47b8c2eb392e98ad5527e2dd5488aee83bea9d5865f11cdcfb9d80975d853