7.2 - USN-3880-1

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

- Ubuntu 14.04 LTS

Summary:

Several security issues were fixed in the Linux kernel.

Software Description: - linux: Linux kernel

Details:

It was discovered that the CIFS client implementation in the Linux kernel did not properly handle setup negotiation during session recovery, leading to a NULL pointer exception. An attacker could use this to create a malicious CIFS server that caused a denial of service (client system crash). (CVE-2018-1066)

Jann Horn discovered that the procfs file system implementation in the Linux kernel did not properly restrict the ability to inspect the kernel stack of an arbitrary task. A local attacker could use this to expose sensitive information. (CVE-2018-17972)

Jann Horn discovered that the mremap() system call in the Linux kernel did not properly flush the TLB when completing, potentially leaving access to a physical page after it has been released to the page allocator. A local attacker could use this to cause a denial of service (system crash), expose sensitive information, or possibly execute arbitrary code. (CVE-2018-18281)

It was discovered that the socket implementation in the Linux kernel contained a type confusion error that could lead to memory corruption. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2018-9568)

Update instructions:

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

Ubuntu 14.04 LTS:
linux-image-3.13.0-165-generic 3.13.0-165.215
linux-image-3.13.0-165-generic-lpae 3.13.0-165.215
linux-image-3.13.0-165-lowlatency 3.13.0-165.215
linux-image-3.13.0-165-powerpc-e500 3.13.0-165.215
linux-image-3.13.0-165-powerpc-e500mc 3.13.0-165.215
linux-image-3.13.0-165-powerpc-smp 3.13.0-165.215
linux-image-3.13.0-165-powerpc64-emb 3.13.0-165.215
linux-image-3.13.0-165-powerpc64-smp 3.13.0-165.215
linux-image-generic 3.13.0.165.175
linux-image-generic-lpae 3.13.0.165.175
linux-image-lowlatency 3.13.0.165.175
linux-image-powerpc-e500 3.13.0.165.175
linux-image-powerpc-e500mc 3.13.0.165.175
linux-image-powerpc-smp 3.13.0.165.175
linux-image-powerpc64-emb 3.13.0.165.175
linux-image-powerpc64-smp 3.13.0.165.175

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:
https://usn.ubuntu.com/usn/usn-3880-1
CVE-2018-1066, CVE-2018-17972, CVE-2018-18281, CVE-2018-9568

Package Information:
https://launchpad.net/ubuntu/+source/linux/3.13.0-165.215