Linux kernel is vulnerable to authorization bypass attacks. This is due to disabled external interrupts in Linux kernel built with the KVM visualization support (CONFIG_KVM), with nested visualization (nVMX) feature enabled (nested=1). A local guest attacker could obtain read and write access to the hardware CR8 register causing an application crash.
git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=51aa68e7d57e3217192d88ce90fd5b8ef29ec94f
www.debian.org/security/2017/dsa-3981
www.securityfocus.com/bid/100856
access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/7.5_Release_Notes/index.html
access.redhat.com/errata/RHSA-2018:0676
access.redhat.com/errata/RHSA-2018:1062
access.redhat.com/errata/RHSA-2019:1946
access.redhat.com/security/cve/CVE-2017-12154
access.redhat.com/security/cve/CVE-2017-13305
access.redhat.com/security/cve/CVE-2017-15274
access.redhat.com/security/updates/classification/#important
bugzilla.redhat.com/show_bug.cgi?id=1292927
bugzilla.redhat.com/show_bug.cgi?id=1401061
bugzilla.redhat.com/show_bug.cgi?id=1430418
bugzilla.redhat.com/show_bug.cgi?id=1448770
bugzilla.redhat.com/show_bug.cgi?id=1452589
bugzilla.redhat.com/show_bug.cgi?id=1462329
bugzilla.redhat.com/show_bug.cgi?id=1491224
bugzilla.redhat.com/show_bug.cgi?id=1500894
bugzilla.redhat.com/show_bug.cgi?id=1503749
bugzilla.redhat.com/show_bug.cgi?id=1506255
bugzilla.redhat.com/show_bug.cgi?id=1507270
bugzilla.redhat.com/show_bug.cgi?id=1509264
bugzilla.redhat.com/show_bug.cgi?id=1518274
bugzilla.redhat.com/show_bug.cgi?id=1518638
github.com/torvalds/linux/commit/51aa68e7d57e3217192d88ce90fd5b8ef29ec94f
usn.ubuntu.com/3698-1/
usn.ubuntu.com/3698-2/
www.spinics.net/lists/kvm/msg155414.html