The system must not send IPv4 Internet Control Message Protocol (ICMP) redirects.

From SUSE Linux Enterprise Server v11 for System z

Part of GEN003610

Associated with: CCI-001551

SV-45727r1_rule The system must not send IPv4 Internet Control Message Protocol (ICMP) redirects.

Vulnerability discussion

ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages contain information from the system's route table possibly revealing portions of the network topology.

Check content

Verify the system does not send IPv4 ICMP redirect messages. # grep [01] /proc/sys/net/ipv4/conf/*/send_redirects|egrep "default|all" If all of the resulting lines do not end with "0", this is a finding.

Fix text

Configure the system to not send IPv4 ICMP redirect messages. Edit /etc/sysctl.conf and add a setting for "net.ipv4.conf.all.send_redirects=0" and "net.ipv4.conf.default.send_redirects=0". # sysctl -p

Pro Tips

Lavender hyperlinks in small type off to the right (of CSS class id, if you view the page source) point to globally unique URIs for each document and item. Copy the link location and paste anywhere you need to talk unambiguously about these things.

You can obtain data about documents and items in other formats. Simply provide an HTTP header Accept: text/turtle or Accept: application/rdf+xml.

Powered by sagemincer