Detections
Analytics

GEN003609 - The system must ignore IPv4 ICMP redirect messages - 'net.ipv4.conf.all.accept_redirects'

Information

ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages modify the host's route table and are unauthenticated. An illicit ICMP redirect message could result in a man-in-the-middle attack.

Solution

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

See Also

http://iasecontent.disa.mil/stigs/zip/U_RedHat_5_V1R18_STIG.zip

Item Details

Category: ACCESS CONTROL, CONFIGURATION MANAGEMENT

References: 800-53|AC-4, 800-53|CM-6d., CAT|II, CCE|CCE-4217-6, CCI|CCI-001503, CCI|CCI-001551, Group-ID|V-22416, Rule-ID|SV-37626r1_rule, STIG-ID|GEN003609, Vuln-ID|V-22416

Plugin: Unix

Control ID: a65d2e5f59e8c4b29ea76e5db2a05c0af1543ba987850222ddc6ded1a773baa6