An incorrect sysctls validation vulnerability was found in CRI-O 1.18 and earlier. The sysctls from the list of "safe" sysctls specified for the cluster will be applied to the host if an attacker is able to create a pod with a hostIPC and hostNetwork kernel namespace.
https://www.ibm.com/support/pages/node/6842157
https://kubernetes.io/docs/tasks/administer-cluster/sysctl-cluster/#enabling-unsafe-sysctls