Ubuntu Security Notice USN-2979-1
16th May, 2016
linux vulnerabilities
A security issue affects these releases of Ubuntu and its
derivatives:
- Ubuntu 16.04 LTS
Summary
Several security issues were fixed in the kernel.
Software description
- 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 version:
- Ubuntu 16.04 LTS:
-
linux-image-4.4.0-22-powerpc-e500mc
4.4.0-22.40
-
linux-image-4.4.0-22-powerpc64-smp
4.4.0-22.40
-
linux-image-4.4.0-22-generic-lpae
4.4.0-22.40
-
linux-image-4.4.0-22-lowlatency
4.4.0-22.40
-
linux-image-4.4.0-22-powerpc-smp
4.4.0-22.40
-
linux-image-4.4.0-22-generic
4.4.0-22.40
-
linux-image-4.4.0-22-powerpc64-emb
4.4.0-22.40
To update your system, please follow these instructions:
https://wiki.ubuntu.com/Security/Upgrades.
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.