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Ubuntu 16.04 LTS: USN-3056-1 Critical Linux Kernel Security Issues

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Calendar Grey August 10, 2016
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Ubuntu 18.04 LTS kernel upgrades address multiple critical vulnerabilities, improving the protection of Raspberry Pi 3 devices.
Several security issues were fixed in the kernel.

Summary

Several security issues were fixed in the kernel.

Software Description:

- linux-raspi2: Linux kernel for Raspberry Pi 2

Details:

Ben Hawkes discovered an integer overflow in the Linux netfilter

implementation. On systems running 32 bit kernels, a local unprivileged

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

possibly execute arbitrary code with administrative privileges.

(CVE-2016-3135)

It was discovered that the keyring implementation in the Linux kernel did

not ensure a data structure was initialized before referencing it after an

error condition occurred. A local attacker could use this to cause a denial

of service (system crash). (CVE-2016-4470)

Sasha Levin discovered that a use-after-free existed in the percpu

allocator in the Linux kernel. A local attacker could use this to cause a

denial of service (system crash) or possibly execute arbitrary code with

administrative privileges. (CVE-2016-4794)

Kangjie Lu discovered an...

Read the Full Advisory

Topics%20covered

Topics Covered

security advisory denial of service critical system crash Raspberry Pi linux-raspi2

Update Instructions

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

Ubuntu 16.04 LTS:
  linux-image-4.4.0-1019-raspi2   4.4.0-1019.25

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-3056-1

CVE-2016-3135, CVE-2016-4470, CVE-2016-4794, CVE-2016-5243

Severity
critical
Lowest
Low
Medium
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Critical

August 10, 2016

Topics%20covered

Topics Covered

security advisory denial of service critical system crash Raspberry Pi linux-raspi2

Package Information

https://launchpad.net/ubuntu/+source/linux-raspi2/4.4.0-1019.25

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