USN-3776-2: Linux kernel (Xenial HWE) vulnerabilities

1 October 2018

linux-lts-xenial, linux-aws vulnerabilities

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-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-lts-xenial - Linux hardware enablement kernel from Xenial for Trusty

Details

USN-3776-1 fixed vulnerabilities in the Linux kernel for Ubuntu 16.04 LTS. This update provides the corresponding updates for the Linux Hardware Enablement (HWE) kernel from Ubuntu 16.04 LTS for Ubuntu 14.04 LTS.

Jann Horn discovered that the vmacache subsystem did not properly handle sequence number overflows, leading to a use-after-free vulnerability. A local attacker could use this to cause a denial of service (system crash) or execute arbitrary code. (CVE-2018-17182)

It was discovered that the paravirtualization implementation in the Linux kernel did not properly handle some indirect calls, reducing the effectiveness of Spectre v2 mitigations for paravirtual guests. A local attacker could use this to expose sensitive information. (CVE-2018-15594)

It was discovered that microprocessors utilizing speculative execution and prediction of return addresses via Return Stack Buffer (RSB) may allow unauthorized memory reads via sidechannel attacks. An attacker could use this to expose sensitive information. (CVE-2018-15572)

It was discovered that a NULL pointer dereference could be triggered in the OCFS2 file system implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash). (CVE-2017-18216)

It was discovered that a race condition existed in the raw MIDI driver for the Linux kernel, leading to a double free vulnerability. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2018-10902)

It was discovered that a stack-based buffer overflow existed in the iSCSI target implementation of the Linux kernel. A remote attacker could use this to cause a denial of service (system crash). (CVE-2018-14633)

It was discovered that the YUREX USB device driver for the Linux kernel did not properly restrict user space reads or writes. A physically proximate attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2018-16276)

It was discovered that a memory leak existed in the IRDA subsystem of the Linux kernel. A local attacker could use this to cause a denial of service (kernel memory exhaustion). (CVE-2018-6554)

It was discovered that a use-after-free vulnerability existed in the IRDA implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2018-6555)

Update instructions

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

Ubuntu 14.04 LTS
linux-image-4.4.0-1031-aws - 4.4.0-1031.34
linux-image-4.4.0-137-generic - 4.4.0-137.163~14.04.1
linux-image-4.4.0-137-generic-lpae - 4.4.0-137.163~14.04.1
linux-image-4.4.0-137-lowlatency - 4.4.0-137.163~14.04.1
linux-image-4.4.0-137-powerpc-e500mc - 4.4.0-137.163~14.04.1
linux-image-4.4.0-137-powerpc-smp - 4.4.0-137.163~14.04.1
linux-image-4.4.0-137-powerpc64-emb - 4.4.0-137.163~14.04.1
linux-image-4.4.0-137-powerpc64-smp - 4.4.0-137.163~14.04.1
linux-image-aws - 4.4.0.1031.31
linux-image-generic-lpae-lts-xenial - 4.4.0.137.117
linux-image-generic-lts-xenial - 4.4.0.137.117
linux-image-lowlatency-lts-xenial - 4.4.0.137.117
linux-image-powerpc-e500mc-lts-xenial - 4.4.0.137.117
linux-image-powerpc-smp-lts-xenial - 4.4.0.137.117
linux-image-powerpc64-emb-lts-xenial - 4.4.0.137.117
linux-image-powerpc64-smp-lts-xenial - 4.4.0.137.117

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