USN-3695-1: Linux kernel vulnerabilities

Releases

• Ubuntu 18.04 ESM

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 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

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

Ubuntu 18.04

• 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

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

• CVE-2018-1094
• CVE-2018-10940
• CVE-2018-1095
• CVE-2018-11508
• CVE-2018-7755

Related notices

• USN-3695-2: linux-image-4.15.0-24-generic, linux-image-unsigned-4.15.0-24-lowlatency, linux-image-unsigned-4.15.0-1014-azure, linux-image-unsigned-4.15.0-24-generic, linux-image-4.15.0-24-lowlatency, linux-hwe, linux-azure, linux-image-4.15.0-24-generic-lpae
• USN-3676-1: linux-image-4.4.0-128-powerpc64-smp, linux-aws, linux-image-4.4.0-1094-snapdragon, linux, linux-image-4.4.0-1091-raspi2, linux-image-4.4.0-128-generic, linux-image-4.4.0-128-lowlatency, linux-image-4.4.0-128-powerpc-e500mc, linux-image-4.4.0-128-powerpc-smp, linux-image-extra-4.4.0-128-generic, linux-image-4.4.0-1027-kvm, linux-snapdragon, linux-kvm, linux-image-4.4.0-128-generic-lpae, linux-image-4.4.0-1061-aws, linux-raspi2, linux-image-4.4.0-128-powerpc64-emb
• USN-3676-2: linux-image-4.4.0-128-powerpc64-smp, linux-aws, linux-image-4.4.0-128-lowlatency, linux-image-4.4.0-128-generic, linux-image-4.4.0-128-powerpc-e500mc, linux-image-4.4.0-128-powerpc-smp, linux-image-extra-4.4.0-128-generic, linux-lts-xenial, linux-image-4.4.0-128-generic-lpae, linux-image-4.4.0-1023-aws, linux-image-4.4.0-128-powerpc64-emb
• USN-3754-1: linux-image-3.13.0-157-powerpc64-smp, linux-image-3.13.0-157-powerpc-e500, linux-image-3.13.0-157-generic-lpae, linux, linux-image-3.13.0-157-powerpc-e500mc, linux-image-3.13.0-157-powerpc-smp, linux-image-3.13.0-157-generic, linux-image-3.13.0-157-lowlatency, linux-image-extra-3.13.0-157-generic, linux-image-3.13.0-157-powerpc64-emb
• USN-3697-1: linux-image-raspi2, linux-image-4.13.0-46-generic, linux, linux-image-4.13.0-46-lowlatency, linux-image-4.13.0-46-generic-lpae, linux-image-generic-lpae, linux-image-lowlatency, linux-image-generic, linux-raspi2, linux-image-4.13.0-1023-raspi2
• USN-3697-2: linux-image-4.13.0-1031-oem, linux-oem
• USN-3698-2: linux-image-generic-lts-trusty, linux-lts-trusty, linux-image-3.13.0-153-generic, linux-image-3.13.0-153-generic-lpae, linux-image-generic-lpae-lts-trusty
• USN-3698-1: linux-image-3.13.0-153-powerpc-smp, linux, linux-image-3.13.0-153-generic, linux-image-extra-3.13.0-153-generic, linux-image-3.13.0-153-powerpc64-smp, linux-image-3.13.0-153-generic-lpae, linux-image-3.13.0-153-powerpc-e500mc, linux-image-3.13.0-153-powerpc64-emb, linux-image-3.13.0-153-lowlatency, linux-image-3.13.0-153-powerpc-e500
• USN-3696-2: linux-image-4.4.0-130-lowlatency, linux-aws, linux-image-4.4.0-130-powerpc-smp, linux-image-4.4.0-130-powerpc-e500mc, linux-lts-xenial, linux-image-4.4.0-130-powerpc64-smp, linux-image-4.4.0-1024-aws, linux-image-4.4.0-130-generic, linux-image-4.4.0-130-generic-lpae, linux-image-4.4.0-130-powerpc64-emb, linux-image-extra-4.4.0-130-generic
• USN-3696-1: linux-image-4.4.0-130-lowlatency, linux-image-4.4.0-130-powerpc64-emb, linux-aws, linux-image-4.4.0-130-powerpc-smp, linux, linux-image-4.4.0-1062-aws, linux-image-4.4.0-130-powerpc-e500mc, linux-snapdragon, linux-image-4.4.0-130-powerpc64-smp, linux-kvm, linux-image-4.4.0-1095-snapdragon, linux-image-4.4.0-1029-kvm, linux-raspi2, linux-image-4.4.0-130-generic, linux-image-4.4.0-130-generic-lpae, linux-image-4.4.0-1092-raspi2, linux-image-extra-4.4.0-130-generic