USN-2854-1: Linux kernel (Vivid HWE) vulnerabilities
20 December 2015
Several security issues were fixed in the kernel.
Releases
Packages
- linux-lts-vivid - Linux hardware enablement kernel from Vivid
Details
Felix Wilhelm discovered a race condition in the Xen paravirtualized
drivers which can cause double fetch vulnerabilities. An attacker in the
paravirtualized guest could exploit this flaw to cause a denial of service
(crash the host) or potentially execute arbitrary code on the host.
(CVE-2015-8550)
Konrad Rzeszutek Wilk discovered the Xen PCI backend driver does not
perform consistency checks on the device's state. An attacker could exploit this
flaw to cause a denial of service (NULL dereference) on the host.
(CVE-2015-8551)
Konrad Rzeszutek Wilk discovered the Xen PCI backend driver does not
perform consistency checks on the device's state. An attacker could exploit this
flaw to cause a denial of service by flooding the logging system with
WARN() messages causing the initial domain to exhaust disk space.
(CVE-2015-8552)
Jann Horn discovered a ptrace issue with user namespaces in the Linux
kernel. The namespace owner could potentially exploit this flaw by ptracing
a root owned process entering the user namespace to elevate its privileges
and potentially gain access outside of the namespace.
(http://bugs.launchpad.net/bugs/1527374, CVE-2015-8709)
Update instructions
The problem can be corrected by updating your system to the following package versions:
Ubuntu 14.04
-
linux-image-3.19.0-42-generic
-
3.19.0-42.48~14.04.1
-
linux-image-3.19.0-42-generic-lpae
-
3.19.0-42.48~14.04.1
-
linux-image-3.19.0-42-lowlatency
-
3.19.0-42.48~14.04.1
-
linux-image-3.19.0-42-powerpc-e500mc
-
3.19.0-42.48~14.04.1
-
linux-image-3.19.0-42-powerpc-smp
-
3.19.0-42.48~14.04.1
-
linux-image-3.19.0-42-powerpc64-emb
-
3.19.0-42.48~14.04.1
-
linux-image-3.19.0-42-powerpc64-smp
-
3.19.0-42.48~14.04.1
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.