Check: OL6-00-000081
Oracle Linux 6 STIG:
OL6-00-000081
(in versions v2 r7 through v1 r9)
Title
The system must not send ICMPv4 redirects from any interface. (Cat II impact)
Discussion
Sending ICMP redirects permits the system to instruct other systems to update their routing information. The ability to send ICMP redirects is only appropriate for systems acting as routers.
Check Content
The status of the "net.ipv4.conf.all.send_redirects" kernel parameter can be queried by running the following command: $ sysctl net.ipv4.conf.all.send_redirects The output of the command should indicate a value of "0". If this value is not the default value, investigate how it could have been adjusted at runtime, and verify it is not set improperly in "/etc/sysctl.conf". $ grep net.ipv4.conf.all.send_redirects /etc/sysctl.conf If the correct value is not returned, this is a finding.
Fix Text
To set the runtime status of the "net.ipv4.conf.all.send_redirects" kernel parameter, run the following command: # sysctl -w net.ipv4.conf.all.send_redirects=0 If this is not the system's default value, add the following line to "/etc/sysctl.conf": net.ipv4.conf.all.send_redirects = 0
Additional Identifiers
Rule ID: SV-208851r793636_rule
Vulnerability ID: V-208851
Group Title: SRG-OS-000480
Expert Comments
CCIs
Number | Definition |
---|---|
CCI-000366 |
The organization implements the security configuration settings. |
Controls
Number | Title |
---|---|
CM-6 |
Configuration Settings |