net/netfilter/xt_osf.c in the Linux kernel through 4.14.4 does not require the CAP_NET_ADMIN capability for add_callback and remove_callback operations, which allows local users to bypass intended access restrictions because the xt_osf_fingers data structure is shared across all network namespaces.
An upstream patch:
Created kernel tracking bugs for this issue:
Affects: fedora-all [bug 1525764]
This issue does not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 5 and Red Hat Enterprise MRG 2, as a code with the flaw is not present or is not built in the products listed.
This issue affects the versions of the Linux kernel as shipped with Red Hat Enterprise Linux 6, 7, its real-time kernel, Red Hat Enterprise Linux 7 for ARM 64 and Red Hat Enterprise Linux 7 for Power 9 LE. This has been rated as having Low security impact and is not currently planned to be addressed in future updates. For additional information, refer to the Red Hat Enterprise Linux Life Cycle: https://access.redhat.com/support/policy/updates/errata/.
What is Red Hat Enterprise Linux 7 for ARM 64,
Red Hat Enterprise Linux 7 for Power 9 LE
The kernel package as shipped with Red Hat Enterprise Linux 7 for ARM 64 and Red Hat Enterprise Linux 7 for Power 9 LE is an updated kernel intended to support new architectures not available at the time of Red Hat Enterprise Linux 7 original shipping. The new kernel version is based on an upstream Linux kernel version 4.11. The offering is distributed with other updated packages, but most of the userspace is the standard Red Hat Enterprise Linux 7 Server RPM files.
For more information please refer to: