1. Ubuntu Security Notices
  2. USN-2890-1

USN-2890-1: Linux kernel vulnerabilities

Publication date

2 February 2016

Overview

Several security issues were fixed in the kernel.

Releases

Packages

Details

It was discovered that a use-after-free vulnerability existed in the
AF_UNIX implementation in the Linux kernel. A local attacker could use
crafted epoll_ctl calls to cause a denial of service (system crash) or
expose sensitive information. (CVE-2013-7446)

It was discovered that the KVM implementation in the Linux kernel did not
properly restore the values of the Programmable Interrupt Timer (PIT). A
user-assisted attacker in a KVM guest could cause a denial of service in
the host (system crash). (CVE-2015-7513)

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)

Sasha Levin discovered that the Reliable Datagram Sockets (RDS)
implementation in the Linux kernel...

It was discovered that a use-after-free vulnerability existed in the
AF_UNIX implementation in the Linux kernel. A local attacker could use
crafted epoll_ctl calls to cause a denial of service (system crash) or
expose sensitive information. (CVE-2013-7446)

It was discovered that the KVM implementation in the Linux kernel did not
properly restore the values of the Programmable Interrupt Timer (PIT). A
user-assisted attacker in a KVM guest could cause a denial of service in
the host (system crash). (CVE-2015-7513)

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)

Sasha Levin discovered that the Reliable Datagram Sockets (RDS)
implementation in the Linux kernel had a race condition when checking
whether a socket was bound or not. A local attacker could use this to cause
a denial of service (system crash). (CVE-2015-7990)

It was discovered that the Btrfs implementation in the Linux kernel
incorrectly handled compressed inline extants on truncation. A local
attacker could use this to expose sensitive information. (CVE-2015-8374)

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 netfilter Network Address Translation (NAT)
implementation did not ensure that data structures were initialized when
handling IPv4 addresses. An attacker could use this to cause a denial of
service (system crash). (CVE-2015-8787)

Update instructions

After a standard system update you need to reboot your computer to make all the necessary changes.

Learn more about how to get the fixes.

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.

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

Ubuntu Release Package Version
15.10 wily linux-image-4.2.0-27-lowlatency –  4.2.0-27.32
linux-image-4.2.0-27-generic-lpae –  4.2.0-27.32
linux-image-4.2.0-27-powerpc-e500mc –  4.2.0-27.32
linux-image-4.2.0-27-powerpc64-emb –  4.2.0-27.32
linux-image-4.2.0-27-powerpc-smp –  4.2.0-27.32
linux-image-4.2.0-27-powerpc64-smp –  4.2.0-27.32
linux-image-4.2.0-27-generic –  4.2.0-27.32

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References

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