The SUSE operating system must not allow interfaces to accept Internet Protocol version 6 (IPv6) Internet Control Message Protocol (ICMP) redirect messages by default.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-217293 | SLES-12-030401 | SV-217293r991589_rule | Medium |
| Description |
| 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. |
| STIG | Date |
| SLES 12 Security Technical Implementation Guide | 2024-11-25 |
Details
| Check Text (C-18521r370035_chk) |
| Verify the SUSE operating system does not allow IPv6 ICMP redirect messages by default. Check the value of the "default accept_redirects" variables with the following command: # sudo sysctl net.ipv6.conf.default.accept_redirects net.ipv6.conf.default.accept_redirects = 0 If the returned line does not have a value of "0", this is a finding. |
| Fix Text (F-18519r370036_fix) |
| Configure the SUSE operating system to not allow IPv6 ICMP redirect messages by default. Set the system to the required kernel parameter by adding the following line to "/etc/sysctl.conf" (or modify the line to have the required value): net.ipv6.conf.default.accept_redirects=0 Run the following command to apply this value: # sysctl –system |