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Ubuntu 14.04 LTS USN-2843-2 Moderate: Kernel Denial Of Service Risks

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Calendar Grey December 17, 2015
Scroller Ubuntu
=========================================================================Ubuntu Security Notice USN-
Several security issues were fixed in the kernel.

Summary

Several security issues were fixed in the kernel.

Software Description:

- linux-lts-wily: Linux hardware enablement kernel from Wily

Details:

Jan Beulich discovered that the KVM svm hypervisor implementation in the

Linux kernel did not properly catch Debug exceptions on AMD processors. An

attacker in a guest virtual machine could use this to cause a denial of

service (system crash) in the host OS. (CVE-2015-8104)

郭永刚 discovered that the ppp implementation in the Linux kernel did

not ensure that certain slot numbers are valid. A local attacker with the

privilege to call ioctl() on /dev/ppp could cause a denial of service

(system crash). (CVE-2015-7799)

Dmitry Vyukov discovered that the Linux kernel's keyring handler attempted

to garbage collect incompletely instantiated keys. A local unprivileged

attacker could use this to cause a denial of service (system crash).

(CVE-2015-7872)

It was discovered that the virtual video osd test driver in the Linux

...

Read the Full Advisory

Topics%20covered

Topics Covered

security advisory denial of service kernel ubuntu system crash

Update Instructions

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

Ubuntu 14.04 LTS:
  linux-image-4.2.0-21-generic    4.2.0-21.25~14.04.1
  linux-image-4.2.0-21-generic-lpae  4.2.0-21.25~14.04.1
  linux-image-4.2.0-21-lowlatency  4.2.0-21.25~14.04.1
  linux-image-4.2.0-21-powerpc-e500mc  4.2.0-21.25~14.04.1
  linux-image-4.2.0-21-powerpc-smp  4.2.0-21.25~14.04.1
  linux-image-4.2.0-21-powerpc64-emb  4.2.0-21.25~14.04.1
  linux-image-4.2.0-21-powerpc64-smp  4.2.0-21.25~14.04.1

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. If
you use linux-restricted-modules, you have to update that package as
well to get modules which work with the new kernel version. Unless you
manually uninstalled the standard kernel metapackages (e.g. linux-generic,
linux-server, linux-powerpc), a standard system upgrade will automatically
perform this as well.

References

https://ubuntu.com/security/notices/USN-2843-2

https://ubuntu.com/security/notices/USN-2843-1

CVE-2015-7799, CVE-2015-7872, CVE-2015-7884, CVE-2015-7885,

CVE-2015-8104

Severity
important
Lowest
Low
Medium
High
Critical

December 17, 2015

Topics%20covered

Topics Covered

security advisory denial of service kernel ubuntu system crash

Package Information

https://launchpad.net/ubuntu/+source/linux-lts-wily/4.2.0-21.25~14.04.1

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