USN-2886-1: Linux kernel vulnerabilities

Ubuntu Security Notice USN-2886-1

1st February, 2016

linux vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

• Ubuntu 12.04 LTS

Summary

Several security issues were fixed in the kernel.

Software description

• linux - Linux kernel

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)

郭永刚 discovered that the ppp implementation in the Linux kernel did
not ensure that certain slot numbers are valid. A local attacker with the
privilege to call ioctl() on /dev/ppp could cause a denial of service
(system crash). (CVE-2015-7799)

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 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 version:

Ubuntu 12.04 LTS:

linux-image-3.2.0-98-omap 3.2.0-98.138

linux-image-3.2.0-98-powerpc-smp 3.2.0-98.138

linux-image-3.2.0-98-generic-pae 3.2.0-98.138

linux-image-3.2.0-98-virtual 3.2.0-98.138

linux-image-3.2.0-98-highbank 3.2.0-98.138

linux-image-3.2.0-98-generic 3.2.0-98.138

linux-image-3.2.0-98-powerpc64-smp 3.2.0-98.138

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

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

CVE-2013-7446, CVE-2015-7513, CVE-2015-7799, CVE-2015-7990, CVE-2015-8374, CVE-2015-8543, CVE-2015-8569, CVE-2015-8575, CVE-2015-8785