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Ubuntu 15.04 USN-2850-1 Medium: Kernel Denial of Service Risks

ubuntu
Calendar Grey December 20, 2015
Scroller Ubuntu
Enhance your Debian installation by applying crucial kernel updates which rectify various critical vulnerabilities identified in November 2016.
Several security issues were fixed in the kernel.

Summary

Several security issues were fixed in the kernel.

Software Description:

- linux: Linux kernel

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 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)

Jann Horn discovered a ptrace issue w...

Read the Full Advisory

Topics%20covered

Topics Covered

security advisory denial of service security issue kernel ubuntu crash

Update Instructions

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

Ubuntu 15.04:
  linux-image-3.19.0-42-generic   3.19.0-42.48
  linux-image-3.19.0-42-generic-lpae  3.19.0-42.48
  linux-image-3.19.0-42-lowlatency  3.19.0-42.48
  linux-image-3.19.0-42-powerpc-e500mc  3.19.0-42.48
  linux-image-3.19.0-42-powerpc-smp  3.19.0-42.48
  linux-image-3.19.0-42-powerpc64-emb  3.19.0-42.48
  linux-image-3.19.0-42-powerpc64-smp  3.19.0-42.48

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

https://ubuntu.com/security/notices/USN-2850-1

CVE-2015-8550, CVE-2015-8551, CVE-2015-8552, https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1527374

Severity
medium
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Low
Medium
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Critical

December 19, 2015

Topics%20covered

Topics Covered

security advisory denial of service security issue kernel ubuntu crash

Package Information

https://launchpad.net/ubuntu/+source/linux/3.19.0-42.48

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