diff --git a/defaults/main.yml b/defaults/main.yml index a85d50e1..f2074034 100644 --- a/defaults/main.yml +++ b/defaults/main.yml @@ -215,6 +215,7 @@ security_disable_module_tipc: yes # V-38517 security_disable_module_usb_storage: no # V-38490 security_disable_icmpv4_redirects: no # V-38524 security_disable_icmpv4_redirects_secure: no # V-38526 +security_disable_icmpv6_redirects: no # V-38548 # # ** DANGER ** # It's strongly recommended to fully understand the effects of changing the diff --git a/doc/source/stig-notes/V-38548_developer.rst b/doc/source/stig-notes/V-38548_developer.rst index 27b4567a..62fd715a 100644 --- a/doc/source/stig-notes/V-38548_developer.rst +++ b/doc/source/stig-notes/V-38548_developer.rst @@ -1,4 +1,15 @@ -**Exception** +**Opt-in required** -Disabling IPv6 redirects can cause issues with OpenStack environments which -have IPv6 enabled and are routing IPv6 traffic. +Accepting ICMP redirects has few legitimate uses. It should be disabled unless +it is absolutely required. + +It is configurable by ``security_disable_icmpv6_redirects`` variable. This +feature is disabled by default. Disabling IPv6 redirects can cause issues with +OpenStack environments which have IPv6 enabled and are routing IPv6 traffic. + +Deployers can opt-in to this change and disable ICMPv6 redirects by setting +the following Ansible variable: + +.. code-block:: yaml + + security_disable_icmpv6_redirects: yes diff --git a/releasenotes/notes/adding-v38548-9c51b30bf9780ff3.yaml b/releasenotes/notes/adding-v38548-9c51b30bf9780ff3.yaml new file mode 100644 index 00000000..297ab134 --- /dev/null +++ b/releasenotes/notes/adding-v38548-9c51b30bf9780ff3.yaml @@ -0,0 +1,8 @@ +--- +features: + - | + A new task was added to disable ICMPv6 redirects per the requirements in + V-38548. However, since this change can cause problems in running OpenStack + environments, it is disabled by default. Deployers who wish to enable this + task (and disable ICMPv6 redirects) should set + ``security_disable_icmpv6_redirects`` to ``yes``. diff --git a/tasks/kernel.yml b/tasks/kernel.yml index 46d6e761..2bf2fb9b 100644 --- a/tasks/kernel.yml +++ b/tasks/kernel.yml @@ -208,3 +208,15 @@ - kernel - cat2 - V-38526 + +- name: V-38548 - The system must ignore ICMPv6 redirects by default + sysctl: + name: net.ipv6.conf.all.accept_redirects + value: 0 + state: present + sysctl_set: yes + when: security_disable_icmpv6_redirects | bool + tags: + - kernel + - cat2 + - V-38548