Title

The system must be configured with a default gateway for IPv4 if the system uses IPv4, unless the system is a router. (Cat II impact)

Discussion

If a system has no default gateway defined, the system is at increased risk of man-in-the-middle, monitoring, and Denial of Service attacks.

Check Content

Check the system for an IPv4 default route. Procedure: # netstat -r |grep default If a default route is not defined, this is a finding.

Fix Text

Create or edit /etc/defaultrouter to contain the default gateway address. Procedure (for a default gateway of 192.168.3.1): # echo "192.168.3.1" > /etc/defaultrouter Restart the system for the setting to take effect.

Additional Identifiers

Rule ID: SV-227909r603266_rule

Vulnerability ID: V-227909

Group Title: SRG-OS-000480

Expert Comments

CCIs tied to check.

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