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

22 February 2016

Several security issues were fixed in the kernel.

Releases

Packages

  • linux-lts-vivid - Linux hardware enablement kernel from Vivid

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)

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.