USN-3070-4: Linux kernel (Xenial HWE) vulnerabilities

30 August 2016

linux-lts-xenial vulnerabilities

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-lts-xenial - Linux hardware enablement kernel from Xenial for Trusty

Details

USN-3070-1 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.

A missing permission check when settings ACLs was discovered in nfsd. A local user could exploit this flaw to gain access to any file by setting an ACL. (CVE-2016-1237)

Kangjie Lu discovered an information leak in the Reliable Datagram Sockets (RDS) implementation in the Linux kernel. A local attacker could use this to obtain potentially sensitive information from kernel memory. (CVE-2016-5244)

James Patrick-Evans discovered that the airspy USB device driver in the Linux kernel did not properly handle certain error conditions. An attacker with physical access could use this to cause a denial of service (memory consumption). (CVE-2016-5400)

Yue Cao et al discovered a flaw in the TCP implementation’s handling of challenge acks in the Linux kernel. A remote attacker could use this to cause a denial of service (reset connection) or inject content into an TCP stream. (CVE-2016-5696)

Pengfei Wang discovered a race condition in the MIC VOP driver in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or obtain potentially sensitive information from kernel memory. (CVE-2016-5728)

Cyril Bur discovered that on PowerPC platforms, the Linux kernel mishandled transactional memory state on exec(). A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2016-5828)

It was discovered that a heap based buffer overflow existed in the USB HID driver in the Linux kernel. A local attacker could use this cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2016-5829)

It was discovered that the OverlayFS implementation in the Linux kernel did not properly verify dentry state before proceeding with unlink and rename operations. A local attacker could use this to cause a denial of service (system crash). (CVE-2016-6197)

Update instructions

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

Ubuntu 14.04 LTS
linux-image-4.4.0-36-generic - 4.4.0-36.55~14.04.1
linux-image-4.4.0-36-generic-lpae - 4.4.0-36.55~14.04.1
linux-image-4.4.0-36-lowlatency - 4.4.0-36.55~14.04.1
linux-image-4.4.0-36-powerpc-e500mc - 4.4.0-36.55~14.04.1
linux-image-4.4.0-36-powerpc-smp - 4.4.0-36.55~14.04.1
linux-image-4.4.0-36-powerpc64-emb - 4.4.0-36.55~14.04.1
linux-image-4.4.0-36-powerpc64-smp - 4.4.0-36.55~14.04.1

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