USN-2978-1: Linux kernel vulnerabilities

Releases

• Ubuntu 15.10

Packages

• linux - Linux kernel

Details

David Matlack discovered that the Kernel-based Virtual Machine (KVM)
implementation in the Linux kernel did not properly restrict variable
Memory Type Range Registers (MTRR) in KVM guests. A privileged user in a
guest VM could use this to cause a denial of service (system crash) in the
host, expose sensitive information from the host, or possibly gain
administrative privileges in the host. (CVE-2016-3713)

Philip Pettersson discovered that the Linux kernel's ASN.1 DER decoder did
not properly process certificate files with tags of indefinite length. A
local unprivileged attacker could use this to cause a denial of service
(system crash) or possibly execute arbitrary code with administrative
privileges. (CVE-2016-0758)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 15.10

• linux-image-4.2.0-36-generic-lpae - 4.2.0-36.42
• linux-image-4.2.0-36-powerpc64-smp - 4.2.0-36.42
• linux-image-4.2.0-36-powerpc64-emb - 4.2.0-36.42
• linux-image-4.2.0-36-powerpc-smp - 4.2.0-36.42
• linux-image-4.2.0-36-powerpc-e500mc - 4.2.0-36.42
• linux-image-4.2.0-36-lowlatency - 4.2.0-36.42
• linux-image-4.2.0-36-generic - 4.2.0-36.42

After a standard system update you need to reboot your computer to make
all the necessary changes.

ATTENTION: Due to an unavoidable ABI change the kernel updates have
been given a new version number, which requires you to recompile and
reinstall all third party kernel modules you might have installed.
Unless you manually uninstalled the standard kernel metapackages
(e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual,
linux-powerpc), a standard system upgrade will automatically perform
this as well.

References

• CVE-2016-0758
• CVE-2016-3713

Related notices

• USN-2975-1: linux-image-3.13.0-86-powerpc-e500mc, linux-image-3.13.0-86-generic, linux-image-3.13.0-86-powerpc64-smp, linux-image-3.13.0-86-powerpc-e500, linux-image-extra-3.13.0-86-generic, linux, linux-image-3.13.0-86-powerpc64-emb, linux-image-3.13.0-86-generic-lpae, linux-image-3.13.0-86-powerpc-smp, linux-image-3.13.0-86-lowlatency
• USN-2978-2: linux-image-extra-4.2.0-36-generic, linux-image-4.2.0-36-generic-lpae, linux-image-4.2.0-36-powerpc64-smp, linux-lts-wily, linux-image-4.2.0-36-lowlatency, linux-image-4.2.0-36-powerpc-e500mc, linux-image-4.2.0-36-powerpc-smp, linux-image-4.2.0-36-generic, linux-image-4.2.0-36-powerpc64-emb
• USN-2976-1: linux-image-3.16.0-71-powerpc-smp, linux-image-3.16.0-71-lowlatency, linux-image-3.16.0-71-generic, linux-image-3.16.0-71-powerpc64-emb, linux-image-3.16.0-71-generic-lpae, linux-image-3.16.0-71-powerpc-e500mc, linux-image-extra-3.16.0-71-generic, linux-lts-utopic, linux-image-3.16.0-71-powerpc64-smp
• USN-2979-4: linux-snapdragon, linux-image-4.4.0-1013-snapdragon
• USN-2977-1: linux-image-3.19.0-59-generic-lpae, linux-image-3.19.0-59-powerpc-e500mc, linux-lts-vivid, linux-image-3.19.0-59-generic, linux-image-3.19.0-59-powerpc64-emb, linux-image-3.19.0-59-powerpc64-smp, linux-image-3.19.0-59-powerpc-smp, linux-image-extra-3.19.0-59-generic, linux-image-3.19.0-59-lowlatency
• USN-2978-3: linux-raspi2, linux-image-4.2.0-1029-raspi2
• USN-2979-2: linux-image-4.4.0-22-generic-lpae, linux-image-4.4.0-22-powerpc64-smp, linux-lts-xenial, linux-image-extra-4.4.0-22-generic, linux-image-4.4.0-22-powerpc-smp, linux-image-4.4.0-22-powerpc64-emb, linux-image-4.4.0-22-powerpc-e500mc, linux-image-4.4.0-22-generic, linux-image-4.4.0-22-lowlatency
• USN-2979-1: linux-image-4.4.0-22-generic-lpae, linux-image-4.4.0-22-powerpc64-smp, linux-image-extra-4.4.0-22-generic, linux-image-4.4.0-22-powerpc-smp, linux-image-4.4.0-22-powerpc64-emb, linux, linux-image-4.4.0-22-powerpc-e500mc, linux-image-4.4.0-22-generic, linux-image-4.4.0-22-lowlatency
• USN-2975-2: linux-image-3.13.0-86-generic-lpae, linux-lts-trusty, linux-image-3.13.0-86-generic
• USN-2979-3: linux-image-4.4.0-1010-raspi2, linux-raspi2