1. Ubuntu Security Notices
  2. USN-3695-1

USN-3695-1: Linux kernel vulnerabilities

Publication date

2 July 2018

Overview

Several security issues were fixed in the Linux kernel.

Releases

Packages

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-azure - Linux kernel for Microsoft Azure Cloud systems
  • linux-gcp - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-kvm - Linux kernel for cloud environments
  • linux-oem - Linux kernel for OEM processors
  • linux-raspi2 - Linux kernel for Raspberry Pi 2

Details

Wen Xu discovered that the ext4 filesystem implementation in the Linux
kernel did not properly initialize the crc32c checksum driver. A local
attacker could use this to cause a denial of service (system crash).
(CVE-2018-1094)

It was discovered that the cdrom driver in the Linux kernel contained an
incorrect bounds check. A local attacker could use this to expose sensitive
information (kernel memory). (CVE-2018-10940)

Wen Xu discovered that the ext4 file system implementation in the Linux
kernel did not properly validate xattr sizes. A local attacker could use
this to cause a denial of service (system crash). (CVE-2018-1095)

Jann Horn discovered that the 32 bit adjtimex() syscall implementation for
64 bit Linux kernels did not properly initialize memory returned to user
space in some situations. A local...

Wen Xu discovered that the ext4 filesystem implementation in the Linux
kernel did not properly initialize the crc32c checksum driver. A local
attacker could use this to cause a denial of service (system crash).
(CVE-2018-1094)

It was discovered that the cdrom driver in the Linux kernel contained an
incorrect bounds check. A local attacker could use this to expose sensitive
information (kernel memory). (CVE-2018-10940)

Wen Xu discovered that the ext4 file system implementation in the Linux
kernel did not properly validate xattr sizes. A local attacker could use
this to cause a denial of service (system crash). (CVE-2018-1095)

Jann Horn discovered that the 32 bit adjtimex() syscall implementation for
64 bit Linux kernels did not properly initialize memory returned to user
space in some situations. A local attacker could use this to expose
sensitive information (kernel memory). (CVE-2018-11508)

It was discovered that an information leak vulnerability existed in the
floppy driver in the Linux kernel. A local attacker could use this to
expose sensitive information (kernel memory). (CVE-2018-7755)

Update instructions

After a standard system update you need to reboot your computer to make all the necessary changes.

Learn more about how to get the fixes.

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.

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

Ubuntu Release Package Version
18.04 bionic linux-image-4.15.0-1010-gcp –  4.15.0-1010.10
linux-image-4.15.0-1011-aws –  4.15.0-1011.11
linux-image-4.15.0-1012-kvm –  4.15.0-1012.12
linux-image-4.15.0-1013-raspi2 –  4.15.0-1013.14
linux-image-4.15.0-24-generic –  4.15.0-24.26
linux-image-4.15.0-24-generic-lpae –  4.15.0-24.26
linux-image-4.15.0-24-lowlatency –  4.15.0-24.26
linux-image-4.15.0-24-snapdragon –  4.15.0-24.26

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References

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