USN-4157-1: Linux kernel vulnerabilities

17 October 2019

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

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

  • Ubuntu 19.04

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-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
  • linux-snapdragon - Linux kernel for Snapdragon processors

Details

Wen Huang discovered that the Marvell Wi-Fi device driver in the Linux kernel did not properly perform bounds checking, leading to a heap overflow. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-14814, CVE-2019-14815, CVE-2019-14816)

Matt Delco discovered that the KVM hypervisor implementation in the Linux kernel did not properly perform bounds checking when handling coalesced MMIO write operations. A local attacker with write access to /dev/kvm could use this to cause a denial of service (system crash). (CVE-2019-14821)

Hui Peng and Mathias Payer discovered that the 91x Wi-Fi driver in the Linux kernel did not properly handle error conditions on initialization, leading to a double-free vulnerability. A physically proximate attacker could use this to cause a denial of service (system crash). (CVE-2019-15504)

It was discovered that the Technisat DVB-S/S2 USB device driver in the Linux kernel contained a buffer overread. A physically proximate attacker could use this to cause a denial of service (system crash) or possibly expose sensitive information. (CVE-2019-15505)

Brad Spengler discovered that a Spectre mitigation was improperly implemented in the ptrace susbsystem of the Linux kernel. A local attacker could possibly use this to expose sensitive information. (CVE-2019-15902)

It was discovered that the IPv6 RDS implementation in the Linux kernel did not properly initialize fields in a data structure returned to user space. A local attacker could use this to expose sensitive information (kernel memory). Please note that the RDS protocol is blacklisted in Ubuntu by default. (CVE-2019-16714)

It was discovered that an integer overflow existed in the Binder implementation of the Linux kernel, leading to a buffer overflow. A local attacker could use this to escalate privileges. (CVE-2019-2181)

Update instructions

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

Ubuntu 19.04
linux-image-5.0.0-1019-aws - 5.0.0-1019.21
linux-image-5.0.0-1020-kvm - 5.0.0-1020.21
linux-image-5.0.0-1020-raspi2 - 5.0.0-1020.20
linux-image-5.0.0-1021-gcp - 5.0.0-1021.21
linux-image-5.0.0-1023-azure - 5.0.0-1023.24
linux-image-5.0.0-1024-snapdragon - 5.0.0-1024.25
linux-image-5.0.0-32-generic - 5.0.0-32.34
linux-image-5.0.0-32-generic-lpae - 5.0.0-32.34
linux-image-5.0.0-32-lowlatency - 5.0.0-32.34
linux-image-aws - 5.0.0.1019.20
linux-image-azure - 5.0.0.1023.22
linux-image-gcp - 5.0.0.1021.47
linux-image-generic - 5.0.0.32.33
linux-image-generic-lpae - 5.0.0.32.33
linux-image-gke - 5.0.0.1021.47
linux-image-kvm - 5.0.0.1020.20
linux-image-lowlatency - 5.0.0.32.33
linux-image-raspi2 - 5.0.0.1020.17
linux-image-snapdragon - 5.0.0.1024.17
linux-image-virtual - 5.0.0.32.33

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