5.9 - USN-2887-1

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

- Ubuntu 14.04 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)

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)

Update instructions:

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

Ubuntu 14.04 LTS:
linux-image-3.13.0-77-generic 3.13.0-77.121
linux-image-3.13.0-77-generic-lpae 3.13.0-77.121
linux-image-3.13.0-77-lowlatency 3.13.0-77.121
linux-image-3.13.0-77-powerpc-e500 3.13.0-77.121
linux-image-3.13.0-77-powerpc-e500mc 3.13.0-77.121
linux-image-3.13.0-77-powerpc-smp 3.13.0-77.121
linux-image-3.13.0-77-powerpc64-emb 3.13.0-77.121
linux-image-3.13.0-77-powerpc64-smp 3.13.0-77.121

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:
http://www.ubuntu.com/usn/usn-2887-1
CVE-2013-7446, CVE-2015-7513, CVE-2015-7990, CVE-2015-8374

Package Information:
https://launchpad.net/ubuntu/+source/linux/3.13.0-77.121