Debian: DSA-4369-1 Critical Xen Update: Denial Of Service

Multiple vulnerabilities have been discovered in the Xen hypervisor:

CVE-2018-19961 / CVE-2018-19962

Paul Durrant discovered that incorrect TLB handling could result in
denial of service, privilege escalation or information leaks.

CVE-2018-19965

Matthew Daley discovered that incorrect handling of the INVPCID
instruction could result in denial of service by PV guests.

CVE-2018-19966

It was discovered that a regression in the fix to address
CVE-2017-15595 could result in denial of service, privilege
escalation or information leaks by a PV guest.

CVE-2018-19967

It was discovered that an error in some Intel CPUs could result in
denial of service by a guest instance.

For the stable distribution (stretch), these problems have been fixed in
version 4.8.5+shim4.10.2+xsa282-1+deb9u11.

We recommend that you upgrade your xen packages.

For the detailed security status of xen please refer to
its security tracker page at:
https://security-tracker.debian.org/tracker/source-pac...