The grub2 package before 2.02-0.29 in Red Hat Enterprise Linux (RHEL) 7, when used on UEFI systems, allows local users to bypass intended Secure Boot restrictions and execute non-verified code via a crafted (1) multiboot or (2) multiboot2 module in the configuration file or physically proximate attackers to bypass intended Secure Boot restrictions and execute non-verified code via the (3) boot menu.
https://bugzilla.redhat.com/show_bug.cgi?id=1264103
http://www.securitytracker.com/id/1034198
http://www.securityfocus.com/bid/77983
http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html
http://rhn.redhat.com/errata/RHSA-2015-2401.html
http://lists.fedoraproject.org/pipermail/package-announce/2015-November/172942.html
http://lists.fedoraproject.org/pipermail/package-announce/2015-November/172611.html