arch/x86/entry/entry_64.S in the Linux kernel before 4.1.6 on the x86_64 platform mishandles IRET faults in processing NMIs that occurred during userspace execution, which might allow local users to gain privileges by triggering an NMI.

References

• https://nvd.nist.gov/vuln/detail/CVE-2015-5157
• torvalds/linux@9b6e6a8
• http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=9b6e6a8334d56354853f9c255d1395c2ba570e0a
• http://lists.opensuse.org/opensuse-security-announce/2015-10/msg00009.html
• http://lists.opensuse.org/opensuse-security-announce/2015-11/msg00035.html
• http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00026.html
• http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00031.html
• http://lists.opensuse.org/opensuse-security-announce/2016-02/msg00013.html
• http://rhn.redhat.com/errata/RHSA-2016-0185.html
• http://rhn.redhat.com/errata/RHSA-2016-0212.html
• http://rhn.redhat.com/errata/RHSA-2016-0224.html
• http://rhn.redhat.com/errata/RHSA-2016-0715.html
• http://www.debian.org/security/2015/dsa-3313
• http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.6
• http://www.openwall.com/lists/oss-security/2015/07/22/7
• http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.html
• http://www.oracle.com/technetwork/topics/security/linuxbulletinjan2016-2867209.html
• http://www.securityfocus.com/bid/76005
• http://www.ubuntu.com/usn/USN-2687-1
• http://www.ubuntu.com/usn/USN-2688-1
• http://www.ubuntu.com/usn/USN-2689-1
• http://www.ubuntu.com/usn/USN-2690-1
• http://www.ubuntu.com/usn/USN-2691-1
• https://access.redhat.com/errata/RHSA-2016:0185
• https://access.redhat.com/errata/RHSA-2016:0212
• https://access.redhat.com/errata/RHSA-2016:0224
• https://access.redhat.com/errata/RHSA-2016:0715
• https://access.redhat.com/security/cve/CVE-2015-5157
• https://bugzilla.redhat.com/show_bug.cgi?id=1259577