Debian 9: DSA-4196-1 Critical: Linux Kernel Privilege Escalation

CVE-2018-1087

Andy Lutomirski discovered that the KVM implementation did not
properly handle #DB exceptions while deferred by MOV SS/POP SS,
allowing an unprivileged KVM guest user to crash the guest or
potentially escalate their privileges.

CVE-2018-8897

Nick Peterson of Everdox Tech LLC discovered that #DB exceptions
that are deferred by MOV SS or POP SS are not properly handled,
allowing an unprivileged user to crash the kernel and cause a denial
of service.

For the oldstable distribution (jessie), these problems have been fixed
in version 3.16.56-1+deb8u1. This update includes various fixes for
regressions from 3.16.56-1 as released in DSA-4187-1 (Cf. #897427,
#898067 and #898100).

For the stable distribution (stretch), these problems have been fixed in
version 4.9.88-1+deb9u1. The fix for CVE-2018-1108 applied in DSA-4188-1
is temporarily reverted due to various regression, cf. #897599.

We recommend that you upgrade your linux packages.

For the detailed security s...