A security flaw is present in nl80211_set_rekey_data() function in the Linux kernel since v3.1-rc1 through v4.13. This function does not check whether required attributes are present in a netlink request. This request can be issued by a user with CAP_NET_ADMIN privilege and may result in NULL dereference and a system crash.
An analysis shows that NL80211_CMD_SET_REKEY_OFFLOAD request should be issued for a WiFi interface connected to a wireless network. This means that an attacker should be a privileged user already or should be root in a user+net namespace to which a WiFi interface was moved from a main net namespace. We believe the later configuration to be unlikely.
Suggested upstream patch:
Name: bo Zhang
Created kernel tracking bugs for this issue:
Affects: fedora-all [bug 1491057]
This issue does not affect the versions of the Linux kernel as shipped with Red Hat Enterprise Linux 5 as the code with the flaw is not present in this product.
This issue affects the Linux kernel packages as shipped with Red Hat Enterprise Linux 6, 7 and MRG-2. 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/.