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Alerts This Week
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Ubuntu 15.10: USN-2858-3 Critical: Linux Kernel OverlayFS Flaw

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Calendar Grey January 5, 2016
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The Ubuntu Security Advisory USN-2950-4 highlights vulnerabilities affecting Raspberry Pi 3's kernel, posing risks to system integrity with potential elevation of privileges.
The system could be made to run programs as an administrator.

Summary

The system could be made to run programs as an administrator.

Software Description:

- linux-raspi2: Linux kernel for Raspberry Pi 2

Details:

Nathan Williams discovered that overlayfs in the Linux kernel incorrectly

handled setattr operations. A local unprivileged attacker could use this to

create files with administrative permission attributes and execute

arbitrary code with elevated privileges.

Topics%20covered

Topics Covered

security advisory local attack kernel issue ubuntu elevated privileges overlayfs

Update Instructions

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

Ubuntu 15.10:
  linux-image-4.2.0-1018-raspi2   4.2.0-1018.25

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-2858-3

https://ubuntu.com/security/notices/USN-2858-1

CVE-2015-8660

Severity
critical
Lowest
Low
Medium
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Critical

January 05, 2016

Topics%20covered

Topics Covered

security advisory local attack kernel issue ubuntu elevated privileges overlayfs

Package Information

https://launchpad.net/ubuntu/+source/linux-raspi2/4.2.0-1018.25

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