USN-2910-1: Linux kernel (Vivid HWE) vulnerabilities

22 February 2016

Several security issues were fixed in the kernel.

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Releases

Packages

Details

halfdog discovered that OverlayFS, when mounting on top of a FUSE mount,
incorrectly propagated file attributes, including setuid. A local
unprivileged attacker could use this to gain privileges. (CVE-2016-1576)

halfdog discovered that OverlayFS in the Linux kernel incorrectly
propagated security sensitive extended attributes, such as POSIX ACLs. A
local unprivileged attacker could use this to gain privileges.
(CVE-2016-1575)

It was discovered that the Linux kernel keyring subsystem contained a race
between read and revoke operations. A local attacker could use this to
cause a denial of service (system crash). (CVE-2015-7550)

郭永刚 discovered that the Linux kernel networking implementation did
not validate protocol identifiers for certain protocol families, A local
attacker could use this to cause a denial of service (system crash) or
possibly gain administrative privileges. (CVE-2015-8543)

Dmitry Vyukov discovered that the pptp implementation in the Linux kernel
did not verify an address length when setting up a socket. A local attacker
could use this to craft an application that exposed sensitive information
from kernel memory. (CVE-2015-8569)

David Miller discovered that the Bluetooth implementation in the Linux
kernel did not properly validate the socket address length for Synchronous
Connection-Oriented (SCO) sockets. A local attacker could use this to
expose sensitive information. (CVE-2015-8575)

It was discovered that the Linux kernel's Filesystem in Userspace (FUSE)
implementation did not handle initial zero length segments properly. A
local attacker could use this to cause a denial of service (unkillable
task). (CVE-2015-8785)

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Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

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

Ubuntu 14.04

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.