Since {{kernel link|rhel6-testing|042stab114.5}}:

* A flaw was found in the way the Linux kernel handled IRET faults during the processing of NMIs. An unprivileged, local user could use this flaw to crash the system or, potentially (although highly unlikely), escalate their privileges on the system. (CVE-2015-5157)

* A race condition flaw was found in the way the Linux kernel's SCTP implementation handled sctp_accept() during the processing of heartbeat timeout events. A remote attacker could use this flaw to prevent further connections to be accepted by the SCTP server running on the system, resulting in a denial of service. (CVE-2015-8767)