USN-3753-1: Linux kernel vulnerabilities

24 August 2018

linux, linux-aws, linux-kvm, linux-raspi2, linux-snapdragon vulnerabilities

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

  • Ubuntu 16.04 LTS

Summary

Several security issues were fixed in the Linux kernel.

Software Description

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-kvm - Linux kernel for cloud environments
  • linux-raspi2 - Linux kernel for Raspberry Pi 2
  • linux-snapdragon - Linux kernel for Snapdragon processors

Details

It was discovered that the generic SCSI driver in the Linux kernel did not properly enforce permissions on kernel memory access. A local attacker could use this to expose sensitive information or possibly elevate privileges. (CVE-2017-13168)

Wen Xu discovered that a use-after-free vulnerability existed in the ext4 filesystem implementation in the Linux kernel. An attacker could use this to construct a malicious ext4 image that, when mounted, could cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2018-10876, CVE-2018-10879)

Wen Xu discovered that a buffer overflow existed in the ext4 filesystem implementation in the Linux kernel. An attacker could use this to construct a malicious ext4 image that, when mounted, could cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2018-10877)

Wen Xu discovered that an out-of-bounds write vulnerability existed in the ext4 filesystem implementation in the Linux kernel. An attacker could use this to construct a malicious ext4 image that, when mounted, could cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2018-10878, CVE-2018-10882)

Wen Xu discovered that the ext4 filesystem implementation in the Linux kernel did not properly keep meta-data information consistent in some situations. An attacker could use this to construct a malicious ext4 image that, when mounted, could cause a denial of service (system crash). (CVE-2018-10881)

Shankara Pailoor discovered that the JFS filesystem implementation in the Linux kernel contained a buffer overflow when handling extended attributes. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2018-12233)

Wen Xu discovered that the XFS filesystem implementation in the Linux kernel did not properly handle an error condition with a corrupted xfs image. An attacker could use this to construct a malicious xfs image that, when mounted, could cause a denial of service (system crash). (CVE-2018-13094)

It was discovered that the Linux kernel did not properly handle setgid file creation when performed by a non-member of the group. A local attacker could use this to gain elevated privileges. (CVE-2018-13405)

Silvio Cesare discovered that the generic VESA frame buffer driver in the Linux kernel contained an integer overflow. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2018-13406)

Update instructions

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

Ubuntu 16.04 LTS
linux-image-4.4.0-1032-kvm - 4.4.0-1032.38
linux-image-4.4.0-1066-aws - 4.4.0-1066.76
linux-image-4.4.0-1095-raspi2 - 4.4.0-1095.103
linux-image-4.4.0-1099-snapdragon - 4.4.0-1099.104
linux-image-4.4.0-134-generic - 4.4.0-134.160
linux-image-4.4.0-134-generic-lpae - 4.4.0-134.160
linux-image-4.4.0-134-lowlatency - 4.4.0-134.160
linux-image-4.4.0-134-powerpc-e500mc - 4.4.0-134.160
linux-image-4.4.0-134-powerpc-smp - 4.4.0-134.160
linux-image-4.4.0-134-powerpc64-emb - 4.4.0-134.160
linux-image-4.4.0-134-powerpc64-smp - 4.4.0-134.160
linux-image-aws - 4.4.0.1066.68
linux-image-generic - 4.4.0.134.140
linux-image-generic-lpae - 4.4.0.134.140
linux-image-kvm - 4.4.0.1032.31
linux-image-lowlatency - 4.4.0.134.140
linux-image-powerpc-e500mc - 4.4.0.134.140
linux-image-powerpc-smp - 4.4.0.134.140
linux-image-powerpc64-emb - 4.4.0.134.140
linux-image-powerpc64-smp - 4.4.0.134.140
linux-image-raspi2 - 4.4.0.1095.95
linux-image-snapdragon - 4.4.0.1099.91

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