USN-2846-1: Linux kernel vulnerabilities
19 December 2015
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 12.04 LTS
Several security issues were fixed in the kernel.
- linux - Linux kernel
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 sanity 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 sanity 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)
The problem can be corrected by updating your system to the following package versions:
- Ubuntu 12.04 LTS
- linux-image-3.2.0-97-generic - 3.2.0-97.137
- linux-image-3.2.0-97-generic-pae - 3.2.0-97.137
- linux-image-3.2.0-97-highbank - 3.2.0-97.137
- linux-image-3.2.0-97-omap - 3.2.0-97.137
- linux-image-3.2.0-97-powerpc-smp - 3.2.0-97.137
- linux-image-3.2.0-97-powerpc64-smp - 3.2.0-97.137
- linux-image-3.2.0-97-virtual - 3.2.0-97.137
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.