USN-4116-1: Linux kernel vulnerabilities

2 September 2019

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 a use-after-free error existed in the block layer subsystem of the Linux kernel when certain failure conditions occurred. A local attacker could possibly use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2018-20856)

Amit Klein and Benny Pinkas discovered that the Linux kernel did not sufficiently randomize IP ID values generated for connectionless networking protocols. A remote attacker could use this to track particular Linux devices. (CVE-2019-10638)

Praveen Pandey discovered that the Linux kernel did not properly validate sent signals in some situations on PowerPC systems with transactional memory disabled. A local attacker could use this to cause a denial of service. (CVE-2019-13648)

It was discovered that the floppy driver in the Linux kernel did not properly validate meta data, leading to a buffer overread. A local attacker could use this to cause a denial of service (system crash). (CVE-2019-14283)

It was discovered that the floppy driver in the Linux kernel did not properly validate ioctl() calls, leading to a division-by-zero. A local attacker could use this to cause a denial of service (system crash). (CVE-2019-14284)

Jason Wang discovered that an infinite loop vulnerability existed in the virtio net driver in the Linux kernel. A local attacker in a guest VM could possibly use this to cause a denial of service in the host system. (CVE-2019-3900)

Update instructions

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

Ubuntu 16.04 LTS
linux-image-4.4.0-1056-kvm - 4.4.0-1056.63
linux-image-4.4.0-1092-aws - 4.4.0-1092.103
linux-image-4.4.0-1120-raspi2 - 4.4.0-1120.129
linux-image-4.4.0-1124-snapdragon - 4.4.0-1124.130
linux-image-4.4.0-161-generic - 4.4.0-161.189
linux-image-4.4.0-161-generic-lpae - 4.4.0-161.189
linux-image-4.4.0-161-lowlatency - 4.4.0-161.189
linux-image-4.4.0-161-powerpc-e500mc - 4.4.0-161.189
linux-image-4.4.0-161-powerpc-smp - 4.4.0-161.189
linux-image-4.4.0-161-powerpc64-emb - 4.4.0-161.189
linux-image-4.4.0-161-powerpc64-smp - 4.4.0-161.189
linux-image-aws - 4.4.0.1092.96
linux-image-generic - 4.4.0.161.169
linux-image-generic-lpae - 4.4.0.161.169
linux-image-kvm - 4.4.0.1056.56
linux-image-lowlatency - 4.4.0.161.169
linux-image-powerpc-e500mc - 4.4.0.161.169
linux-image-powerpc-smp - 4.4.0.161.169
linux-image-powerpc64-emb - 4.4.0.161.169
linux-image-powerpc64-smp - 4.4.0.161.169
linux-image-raspi2 - 4.4.0.1120.120
linux-image-snapdragon - 4.4.0.1124.116
linux-image-virtual - 4.4.0.161.169

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