A Linux Kernel 4.9 update has been released for Debian GNU/Linux 8 LTS

Package : linux-4.9
Version : 4.9.189-3+deb9u1~deb8u1
CVE ID : CVE-2019-14821 CVE-2019-14835 CVE-2019-15117 CVE-2019-15118
CVE-2019-15902

Several vulnerabilities have been discovered in the Linux kernel that
may lead to a privilege escalation, denial of service or information
leaks.

CVE-2019-14821

Matt Delco reported a race condition in KVM's coalesced MMIO
facility, which could lead to out-of-bounds access in the kernel.
A local attacker permitted to access /dev/kvm could use this to
cause a denial of service (memory corruption or crash) or possibly
for privilege escalation.

CVE-2019-14835

Peter Pi of Tencent Blade Team discovered a missing bounds check
in vhost_net, the network back-end driver for KVM hosts, leading
to a buffer overflow when the host begins live migration of a VM.
An attacker in control of a VM could use this to cause a denial of
service (memory corruption or crash) or possibly for privilege
escalation on the host.

CVE-2019-15117

Hui Peng and Mathias Payer reported a missing bounds check in the
usb-audio driver's descriptor parsing code, leading to a buffer
over-read. An attacker able to add USB devices could possibly use
this to cause a denial of service (crash).

CVE-2019-15118

Hui Peng and Mathias Payer reported unbounded recursion in the
usb-audio driver's descriptor parsing code, leading to a stack
overflow. An attacker able to add USB devices could use this to
cause a denial of service (memory corruption or crash) or possibly
for privilege escalation. On the amd64 architecture this is
mitigated by a guard page on the kernel stack, so that it is only
possible to cause a crash.

CVE-2019-15902

Brad Spengler reported that a backporting error reintroduced a
spectre-v1 vulnerability in the ptrace subsystem in the
ptrace_get_debugreg() function.

For Debian 8 "Jessie", these problems have been fixed in version
4.9.189-3+deb9u1~deb8u1.

We recommend that you upgrade your linux-4.9 packages.

Further information about Debian LTS security advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://wiki.debian.org/LTS

  Kernel Update for Debian 8 LTS