USN-4076-1: Linux kernel vulnerabilities

Publication date

25 July 2019

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-kvm - Linux kernel for cloud environments
  • linux-raspi2 - Linux kernel for Raspberry Pi 2

Details

It was discovered that a race condition existed in the Serial Attached SCSI
(SAS) implementation in the Linux kernel. A local attacker could possibly
use this to cause a denial of service (system crash) or execute arbitrary
code. (CVE-2018-20836)

It was discovered that the ext4 file system implementation in the Linux
kernel did not properly zero out memory in some situations. A local
attacker could use this to expose sensitive information (kernel memory).
(CVE-2019-11833)

It was discovered that the Bluetooth Human Interface Device Protocol (HIDP)
implementation in the Linux kernel did not properly verify strings were
NULL terminated in certain situations. A local attacker could use this to
expose sensitive information (kernel memory). (CVE-2019-11884)

It was discovered that the Linux kernel on ARM processors...

It was discovered that a race condition existed in the Serial Attached SCSI
(SAS) implementation in the Linux kernel. A local attacker could possibly
use this to cause a denial of service (system crash) or execute arbitrary
code. (CVE-2018-20836)

It was discovered that the ext4 file system implementation in the Linux
kernel did not properly zero out memory in some situations. A local
attacker could use this to expose sensitive information (kernel memory).
(CVE-2019-11833)

It was discovered that the Bluetooth Human Interface Device Protocol (HIDP)
implementation in the Linux kernel did not properly verify strings were
NULL terminated in certain situations. A local attacker could use this to
expose sensitive information (kernel memory). (CVE-2019-11884)

It was discovered that the Linux kernel on ARM processors allowed a tracing
process to modify a syscall after a seccomp decision had been made on that
syscall. A local attacker could possibly use this to bypass seccomp
restrictions. (CVE-2019-2054)

Hugues Anguelkov discovered that the Broadcom Wifi driver in the Linux
kernel did not properly prevent remote firmware events from being processed
for USB Wifi devices. A physically proximate attacker could use this to
send firmware events to the device. (CVE-2019-9503)

It was discovered that an integer overflow existed in the Freescale
(PowerPC) hypervisor manager in the Linux kernel. A local attacker with
write access to /dev/fsl-hv could use this to cause a denial of service
(system crash) or possibly execute arbitrary code. (CVE-2019-10142)


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:


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