USN-3903-1: Linux kernel vulnerabilities

Releases

• Ubuntu 18.10

Packages

• linux - Linux kernel
• 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-raspi2 - Linux kernel for Raspberry Pi 2

Details

Jason Wang discovered that the vhost net driver in the Linux kernel
contained an out of bounds write vulnerability. An attacker in a guest
virtual machine could use this to cause a denial of service (host system
crash) or possibly execute arbitrary code in the host kernel.
(CVE-2018-16880)

Jann Horn discovered that the userfaultd implementation in the Linux kernel
did not properly restrict access to certain ioctls. A local attacker could
use this possibly to modify files. (CVE-2018-18397)

Jann Horn discovered a race condition in the fork() system call in the
Linux kernel. A local attacker could use this to gain access to services
that cache authorizations. (CVE-2019-6133)

Update instructions

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

Ubuntu 18.10

• linux-image-4.18.0-16-generic-lpae - 4.18.0-16.17
• linux-image-4.18.0-1008-kvm - 4.18.0-1008.8
• linux-image-4.18.0-16-lowlatency - 4.18.0-16.17
• linux-image-gke - 4.18.0.1007.7
• linux-image-generic - 4.18.0.16.17
• linux-image-gcp - 4.18.0.1007.7
• linux-image-4.18.0-16-generic - 4.18.0-16.17
• linux-image-azure - 4.18.0.1013.14
• linux-image-4.18.0-16-snapdragon - 4.18.0-16.17
• linux-image-4.18.0-1013-azure - 4.18.0-1013.13
• linux-image-generic-lpae - 4.18.0.16.17
• linux-image-snapdragon - 4.18.0.16.17
• linux-image-kvm - 4.18.0.1008.8
• linux-image-4.18.0-1007-gcp - 4.18.0-1007.8
• linux-image-lowlatency - 4.18.0.16.17
• linux-image-raspi2 - 4.18.0.1010.7
• linux-image-4.18.0-1010-raspi2 - 4.18.0-1010.12

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-2018-16880
• CVE-2018-18397
• CVE-2019-6133

Related notices

• USN-3903-2: linux-image-4.18.0-16-snapdragon, linux-image-snapdragon-hwe-18.04, linux-image-4.18.0-16-lowlatency, linux-image-azure, linux-image-generic-lpae-hwe-18.04, linux-image-4.18.0-16-generic-lpae, linux-hwe, linux-azure, linux-image-4.18.0-16-generic, linux-image-virtual-hwe-18.04, linux-image-lowlatency-hwe-18.04, linux-image-generic-hwe-18.04, linux-image-4.18.0-1013-azure
• USN-3901-1: linux-image-kvm, linux-image-4.15.0-1032-raspi2, linux-image-generic-lpae-hwe-16.04, linux, linux-image-virtual-hwe-16.04, linux-image-4.15.0-46-lowlatency, linux-image-4.15.0-1034-oem, linux-image-generic-hwe-16.04, linux-image-4.15.0-1033-aws, linux-image-lowlatency-hwe-16.04, linux-image-4.15.0-46-generic-lpae, linux-image-4.15.0-1030-kvm, linux-raspi2, linux-image-4.15.0-1028-gcp, linux-image-lowlatency, linux-image-snapdragon, linux-image-generic-lpae, linux-image-generic-hwe-16.04-edge, linux-image-4.15.0-46-snapdragon, linux-gcp, linux-image-generic, linux-image-oem, linux-image-raspi2, linux-image-4.15.0-1009-oracle, linux-image-oracle, linux-image-gcp, linux-image-lowlatency-hwe-16.04-edge, linux-image-4.15.0-46-generic, linux-image-virtual, linux-image-virtual-hwe-16.04-edge, linux-image-generic-lpae-hwe-16.04-edge, linux-image-aws, linux-kvm, linux-aws, linux-oem, linux-image-gke, linux-oracle
• USN-3901-2: linux-image-generic-lpae-hwe-16.04, linux-image-virtual-hwe-16.04, linux-image-4.15.0-46-lowlatency, linux-image-generic-hwe-16.04, linux-image-lowlatency-hwe-16.04, linux-aws-hwe, linux-image-4.15.0-46-generic-lpae, linux-image-4.15.0-1033-aws, linux-image-4.15.0-1028-gcp, linux-azure, linux-image-4.15.0-1040-azure, linux-image-azure, linux-gcp, linux-image-oem, linux-image-4.15.0-1009-oracle, linux-image-oracle, linux-image-gcp, linux-image-4.15.0-46-generic, linux-hwe, linux-image-aws-hwe, linux-image-gke, linux-oracle
• USN-3934-2: libpolkit-backend-1-0, policykit-1
• USN-3934-1: libpolkit-agent-1-0, libpolkit-gobject-1-0, libpolkit-agent-1-dev, gir1.2-polkit-1.0, libpolkit-backend-1-dev, policykit-1, libpolkit-backend-1-0, policykit-1-doc, libpolkit-gobject-1-dev
• USN-3910-2: linux-image-4.4.0-143-generic-lpae, linux-image-4.4.0-143-lowlatency, linux-image-powerpc64-smp-lts-xenial, linux-image-4.4.0-143-powerpc-e500mc, linux-image-powerpc64-emb-lts-xenial, linux-image-lowlatency-lts-xenial, linux-image-4.4.0-143-generic, linux-lts-xenial, linux-image-4.4.0-143-powerpc-smp, linux-image-virtual-lts-xenial, linux-image-powerpc-e500mc-lts-xenial, linux-image-4.4.0-1039-aws, linux-image-4.4.0-143-powerpc64-emb, linux-image-aws, linux-image-powerpc-smp-lts-xenial, linux-aws, linux-image-generic-lpae-lts-xenial, linux-image-generic-lts-xenial, linux-image-4.4.0-143-powerpc64-smp
• USN-3910-1: linux-image-kvm, linux-image-powerpc-e500mc-lts-vivid, linux-image-virtual-lts-vivid, linux-image-powerpc64-smp, linux, linux-image-generic-lpae-lts-vivid, linux-image-powerpc-e500mc-lts-utopic, linux-image-powerpc-smp-lts-wily, linux-image-4.4.0-143-generic-lpae, linux-image-powerpc64-emb-lts-utopic, linux-image-virtual-lts-utopic, linux-image-4.4.0-143-lowlatency, linux-image-powerpc64-smp-lts-xenial, linux-image-4.4.0-143-powerpc-e500mc, linux-image-powerpc-e500mc-lts-wily, linux-image-powerpc64-emb-lts-xenial, linux-image-powerpc64-smp-lts-wily, linux-raspi2, linux-image-powerpc-smp-lts-vivid, linux-image-4.4.0-1104-raspi2, linux-image-lowlatency-lts-xenial, linux-image-lowlatency-lts-wily, linux-image-powerpc-e500mc, linux-snapdragon, linux-image-lowlatency, linux-image-4.4.0-143-generic, linux-image-powerpc-smp, linux-image-snapdragon, linux-image-generic-lpae, linux-image-4.4.0-143-powerpc-smp, linux-image-powerpc64-smp-lts-vivid, linux-image-generic-lts-vivid, linux-image-generic-lpae-lts-utopic, linux-image-virtual-lts-xenial, linux-image-powerpc-e500mc-lts-xenial, linux-image-generic-lts-utopic, linux-image-generic-lpae-lts-wily, linux-image-lowlatency-lts-utopic, linux-image-generic, linux-image-lowlatency-lts-vivid, linux-image-powerpc64-emb-lts-wily, linux-image-4.4.0-143-powerpc64-emb, linux-image-raspi2, linux-image-4.4.0-1041-kvm, linux-image-4.4.0-1077-aws, linux-image-powerpc-smp-lts-utopic, linux-image-virtual, linux-image-aws, linux-image-powerpc-smp-lts-xenial, linux-kvm, linux-aws, linux-image-generic-lts-wily, linux-image-powerpc64-emb-lts-vivid, linux-image-4.4.0-1108-snapdragon, linux-image-powerpc64-smp-lts-utopic, linux-image-powerpc64-emb, linux-image-generic-lpae-lts-xenial, linux-image-generic-lts-xenial, linux-image-4.4.0-143-powerpc64-smp, linux-image-virtual-lts-wily
• USN-3908-1: linux-image-powerpc64-smp, linux-image-3.13.0-166-powerpc64-emb, linux, linux-image-generic-lts-saucy, linux-image-3.13.0-166-powerpc-e500, linux-image-3.13.0-166-generic-lpae, linux-image-highbank, linux-image-omap, linux-image-generic-lts-raring, linux-image-generic-lpae-lts-trusty, linux-image-3.13.0-166-powerpc64-smp, linux-image-powerpc-e500mc, linux-image-lowlatency, linux-image-3.13.0-166-lowlatency, linux-image-powerpc-smp, linux-image-generic-lts-quantal, linux-image-generic-lpae, linux-image-powerpc-e500, linux-image-lowlatency-pae, linux-image-3.13.0-166-generic, linux-image-generic, linux-image-generic-lpae-lts-saucy, linux-image-generic-pae, linux-image-virtual, linux-image-3.13.0-166-powerpc-smp, linux-image-3.13.0-166-powerpc-e500mc, linux-image-powerpc64-emb, linux-image-generic-lts-trusty
• USN-3908-2: linux-image-generic-lpae-lts-trusty, linux-image-3.13.0-166-generic, linux-image-3.13.0-166-lowlatency, linux-image-3.13.0-166-generic-lpae, linux-lts-trusty, linux-image-generic-lts-trusty