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2019. november 14.

USN-4194-1: postgresql-common vulnerability

postgresql-common vulnerability

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

  • Ubuntu 19.10
  • Ubuntu 19.04
  • Ubuntu 18.04 LTS
  • Ubuntu 16.04 LTS
Summary

postgresql-common could be made to create arbitrary directories.

Software Description
  • postgresql-common - PostgreSQL database-cluster manager
Details

Rich Mirch discovered that the postgresql-common pg_ctlcluster script incorrectly handled directory creation. A local attacker could possibly use this issue to escalate privileges.

Update instructions

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

Ubuntu 19.10
postgresql-common - 204ubuntu0.1
Ubuntu 19.04
postgresql-common - 199ubuntu0.1
Ubuntu 18.04 LTS
postgresql-common - 190ubuntu0.1
Ubuntu 16.04 LTS
postgresql-common - 173ubuntu0.3

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

In general, a standard system update will make all the necessary changes.

References
2019. november 14.

USN-4193-1: Ghostscript vulnerability

ghostscript vulnerability

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

  • Ubuntu 19.10
  • Ubuntu 19.04
  • Ubuntu 18.04 LTS
  • Ubuntu 16.04 LTS
Summary

Ghostscript could be made to crash, access files, or run programs if it opened a specially crafted file.

Software Description
  • ghostscript - PostScript and PDF interpreter
Details

Paul Manfred and Lukas Schauer discovered that Ghostscript incorrectly handled certain PostScript files. If a user or automated system were tricked into processing a specially crafted file, a remote attacker could possibly use this issue to access arbitrary files, execute arbitrary code, or cause a denial of service.

Update instructions

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

Ubuntu 19.10
ghostscript - 9.27~dfsg+0-0ubuntu3.1
libgs9 - 9.27~dfsg+0-0ubuntu3.1
Ubuntu 19.04
ghostscript - 9.26~dfsg+0-0ubuntu7.4
libgs9 - 9.26~dfsg+0-0ubuntu7.4
Ubuntu 18.04 LTS
ghostscript - 9.26~dfsg+0-0ubuntu0.18.04.12
libgs9 - 9.26~dfsg+0-0ubuntu0.18.04.12
Ubuntu 16.04 LTS
ghostscript - 9.26~dfsg+0-0ubuntu0.16.04.12
libgs9 - 9.26~dfsg+0-0ubuntu0.16.04.12

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

In general, a standard system update will make all the necessary changes.

References
2019. november 14.

USN-4192-1: ImageMagick vulnerabilities

imagemagick vulnerabilities

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

  • Ubuntu 19.10
  • Ubuntu 19.04
  • Ubuntu 18.04 LTS
  • Ubuntu 16.04 LTS
Summary

Several security issues were fixed in ImageMagick.

Software Description
  • imagemagick - Image manipulation programs and library
Details

It was discovered that ImageMagick incorrectly handled certain malformed image files. If a user or automated system using ImageMagick were tricked into opening a specially crafted image, an attacker could exploit this to cause a denial of service or possibly execute code with the privileges of the user invoking the program.

Update instructions

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

Ubuntu 19.10
imagemagick - 8:6.9.10.23+dfsg-2.1ubuntu3.1
imagemagick-6.q16 - 8:6.9.10.23+dfsg-2.1ubuntu3.1
libmagick++-6.q16-8 - 8:6.9.10.23+dfsg-2.1ubuntu3.1
libmagickcore-6.q16-6 - 8:6.9.10.23+dfsg-2.1ubuntu3.1
libmagickcore-6.q16-6-extra - 8:6.9.10.23+dfsg-2.1ubuntu3.1
Ubuntu 19.04
imagemagick - 8:6.9.10.14+dfsg-7ubuntu2.3
imagemagick-6.q16 - 8:6.9.10.14+dfsg-7ubuntu2.3
libmagick++-6.q16-8 - 8:6.9.10.14+dfsg-7ubuntu2.3
libmagickcore-6.q16-6 - 8:6.9.10.14+dfsg-7ubuntu2.3
libmagickcore-6.q16-6-extra - 8:6.9.10.14+dfsg-7ubuntu2.3
Ubuntu 18.04 LTS
imagemagick - 8:6.9.7.4+dfsg-16ubuntu6.8
imagemagick-6.q16 - 8:6.9.7.4+dfsg-16ubuntu6.8
libmagick++-6.q16-7 - 8:6.9.7.4+dfsg-16ubuntu6.8
libmagickcore-6.q16-3 - 8:6.9.7.4+dfsg-16ubuntu6.8
libmagickcore-6.q16-3-extra - 8:6.9.7.4+dfsg-16ubuntu6.8
Ubuntu 16.04 LTS
imagemagick - 8:6.8.9.9-7ubuntu5.15
imagemagick-6.q16 - 8:6.8.9.9-7ubuntu5.15
libmagick++-6.q16-5v5 - 8:6.8.9.9-7ubuntu5.15
libmagickcore-6.q16-2 - 8:6.8.9.9-7ubuntu5.15
libmagickcore-6.q16-2-extra - 8:6.8.9.9-7ubuntu5.15

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

In general, a standard system update will make all the necessary changes.

References
2019. november 14.

USN-4191-2: QEMU vulnerabilities

qemu vulnerabilities

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

  • Ubuntu 14.04 ESM
Summary

Several security issues were fixed in QEMU.

Software Description
  • qemu - Machine emulator and virtualizer
Details

USN-4191-2 fixed a vulnerability in QEMU. This update provides the corresponding update for Ubuntu 14.04 ESM.

Original advisory details:

It was discovered that the LSI SCSI adapter emulator implementation in QEMU did not properly validate executed scripts. A local attacker could use this to cause a denial of service. (CVE-2019-12068)

Sergej Schumilo, Cornelius Aschermann and Simon Wörner discovered that the qxl paravirtual graphics driver implementation in QEMU contained a null pointer dereference. A local attacker in a guest could use this to cause a denial of service. (CVE-2019-12155)

Riccardo Schirone discovered that the QEMU bridge helper did not properly validate network interface names. A local attacker could possibly use this to bypass ACL restrictions. (CVE-2019-13164)

It was discovered that a heap-based buffer overflow existed in the SLiRP networking implementation of QEMU. A local attacker in a guest could use this to cause a denial of service or possibly execute arbitrary code in the host. (CVE-2019-14378)

It was discovered that a use-after-free vulnerability existed in the SLiRP networking implementation of QEMU. A local attacker in a guest could use this to cause a denial of service. (CVE-2019-15890)

Update instructions

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

Ubuntu 14.04 ESM
qemu - 2.0.0+dfsg-2ubuntu1.47
qemu-common - 2.0.0+dfsg-2ubuntu1.47
qemu-kvm - 2.0.0+dfsg-2ubuntu1.47
qemu-system-common - 2.0.0+dfsg-2ubuntu1.47
qemu-system-x86 - 2.0.0+dfsg-2ubuntu1.47
qemu-user-static - 2.0.0+dfsg-2ubuntu1.47
qemu-utils - 2.0.0+dfsg-2ubuntu1.47

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

After a standard system update you need to restart all QEMU virtual machines to make all the necessary changes.

References
2019. november 14.

USN-4191-1: QEMU vulnerabilities

qemu vulnerabilities

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

  • Ubuntu 19.10
  • Ubuntu 19.04
  • Ubuntu 18.04 LTS
  • Ubuntu 16.04 LTS
Summary

Several security issues were fixed in QEMU.

Software Description
  • qemu - Machine emulator and virtualizer
Details

It was discovered that the LSI SCSI adapter emulator implementation in QEMU did not properly validate executed scripts. A local attacker could use this to cause a denial of service. (CVE-2019-12068)

Sergej Schumilo, Cornelius Aschermann and Simon Wörner discovered that the qxl paravirtual graphics driver implementation in QEMU contained a null pointer dereference. A local attacker in a guest could use this to cause a denial of service. (CVE-2019-12155)

Riccardo Schirone discovered that the QEMU bridge helper did not properly validate network interface names. A local attacker could possibly use this to bypass ACL restrictions. (CVE-2019-13164)

It was discovered that a heap-based buffer overflow existed in the SLiRP networking implementation of QEMU. A local attacker in a guest could use this to cause a denial of service or possibly execute arbitrary code in the host. (CVE-2019-14378)

It was discovered that a use-after-free vulnerability existed in the SLiRP networking implementation of QEMU. A local attacker in a guest could use this to cause a denial of service. (CVE-2019-15890)

Update instructions

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

Ubuntu 19.10
qemu - 1:4.0+dfsg-0ubuntu9.1
qemu-kvm - 1:4.0+dfsg-0ubuntu9.1
qemu-system-common - 1:4.0+dfsg-0ubuntu9.1
qemu-system-gui - 1:4.0+dfsg-0ubuntu9.1
qemu-system-x86 - 1:4.0+dfsg-0ubuntu9.1
qemu-user-static - 1:4.0+dfsg-0ubuntu9.1
qemu-utils - 1:4.0+dfsg-0ubuntu9.1
Ubuntu 19.04
qemu - 1:3.1+dfsg-2ubuntu3.6
qemu-kvm - 1:3.1+dfsg-2ubuntu3.6
qemu-system-common - 1:3.1+dfsg-2ubuntu3.6
qemu-system-gui - 1:3.1+dfsg-2ubuntu3.6
qemu-system-x86 - 1:3.1+dfsg-2ubuntu3.6
qemu-user-static - 1:3.1+dfsg-2ubuntu3.6
qemu-utils - 1:3.1+dfsg-2ubuntu3.6
Ubuntu 18.04 LTS
qemu - 1:2.11+dfsg-1ubuntu7.20
qemu-kvm - 1:2.11+dfsg-1ubuntu7.20
qemu-system-common - 1:2.11+dfsg-1ubuntu7.20
qemu-system-x86 - 1:2.11+dfsg-1ubuntu7.20
qemu-user-static - 1:2.11+dfsg-1ubuntu7.20
qemu-utils - 1:2.11+dfsg-1ubuntu7.20
Ubuntu 16.04 LTS
qemu - 1:2.5+dfsg-5ubuntu10.42
qemu-kvm - 1:2.5+dfsg-5ubuntu10.42
qemu-system-common - 1:2.5+dfsg-5ubuntu10.42
qemu-system-x86 - 1:2.5+dfsg-5ubuntu10.42
qemu-user-static - 1:2.5+dfsg-5ubuntu10.42
qemu-utils - 1:2.5+dfsg-5ubuntu10.42

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

After a standard system update you need to restart all QEMU virtual machines to make all the necessary changes.

References
2019. november 13.

USN-4186-3: Linux kernel vulnerability

linux vulnerability

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
Details

USN-4186-1 fixed vulnerabilities in the Linux kernel. It was discovered that the kernel fix for CVE-2019-0155 (i915 missing Blitter Command Streamer check) was incomplete on 64-bit Intel x86 systems. This update addresses the issue.

We apologize for the inconvenience.

Original advisory details:

Stephan van Schaik, Alyssa Milburn, Sebastian Österlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel processors using Transactional Synchronization Extensions (TSX) could expose memory contents previously stored in microarchitectural buffers to a malicious process that is executing on the same CPU core. A local attacker could use this to expose sensitive information. (CVE-2019-11135)

It was discovered that the Intel i915 graphics chipsets allowed userspace to modify page table entries via writes to MMIO from the Blitter Command Streamer and expose kernel memory information. A local attacker could use this to expose sensitive information or possibly elevate privileges. (CVE-2019-0155)

Deepak Gupta discovered that on certain Intel processors, the Linux kernel did not properly perform invalidation on page table updates by virtual guest operating systems. A local attacker in a guest VM could use this to cause a denial of service (host system crash). (CVE-2018-12207)

It was discovered that the Intel i915 graphics chipsets could cause a system hang when userspace performed a read from GT memory mapped input output (MMIO) when the product is in certain low power states. A local attacker could use this to cause a denial of service. (CVE-2019-0154)

Hui Peng discovered that the Atheros AR6004 USB Wi-Fi device driver for the Linux kernel did not properly validate endpoint descriptors returned by the device. A physically proximate attacker could use this to cause a denial of service (system crash). (CVE-2019-15098)

It was discovered that a buffer overflow existed in the 802.11 Wi-Fi configuration interface for the Linux kernel when handling beacon settings. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-16746)

Ori Nimron discovered that the AX25 network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17052)

Ori Nimron discovered that the IEEE 802.15.4 Low-Rate Wireless network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17053)

Ori Nimron discovered that the Appletalk network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17054)

Ori Nimron discovered that the modular ISDN network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17055)

Ori Nimron discovered that the Near field Communication (NFC) network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17056)

Nico Waisman discovered that a buffer overflow existed in the Realtek Wi-Fi driver for the Linux kernel when handling Notice of Absence frames. A physically proximate attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-17666)

Maddie Stone discovered that the Binder IPC Driver implementation in the Linux kernel contained a use-after-free vulnerability. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-2215)

Update instructions

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

Ubuntu 16.04 LTS
linux-image-4.4.0-169-generic - 4.4.0-169.198
linux-image-4.4.0-169-generic-lpae - 4.4.0-169.198
linux-image-4.4.0-169-lowlatency - 4.4.0-169.198
linux-image-generic - 4.4.0.169.177
linux-image-generic-lpae - 4.4.0.169.177
linux-image-lowlatency - 4.4.0.169.177
linux-image-virtual - 4.4.0.169.177

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

Please note that mitigating the TSX (CVE-2019-11135) and i915 (CVE-2019-0154) issues requires corresponding microcode and graphics firmware updates respectively.

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
2019. november 13.

USN-4185-3: Linux kernel vulnerability and regression

linux, linux-hwe, linux-oem vulnerability and regression

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

  • Ubuntu 18.04 LTS
  • Ubuntu 16.04 LTS
Summary

Several issues were fixed in the Linux kernel.

Software Description
  • linux - Linux kernel
  • linux-oem - Linux kernel for OEM processors
  • linux-hwe - Linux hardware enablement (HWE) kernel
Details

USN-4185-1 fixed vulnerabilities in the Linux kernel. It was discovered that the kernel fix for CVE-2019-0155 (i915 missing Blitter Command Streamer check) was incomplete on 64-bit Intel x86 systems. Also, the update introduced a regression that broke KVM guests where extended page tables (EPT) are disabled or not supported. This update addresses both issues.

We apologize for the inconvenience.

Original advisory details:

Stephan van Schaik, Alyssa Milburn, Sebastian Österlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel processors using Transactional Synchronization Extensions (TSX) could expose memory contents previously stored in microarchitectural buffers to a malicious process that is executing on the same CPU core. A local attacker could use this to expose sensitive information. (CVE-2019-11135)

It was discovered that the Intel i915 graphics chipsets allowed userspace to modify page table entries via writes to MMIO from the Blitter Command Streamer and expose kernel memory information. A local attacker could use this to expose sensitive information or possibly elevate privileges. (CVE-2019-0155)

Deepak Gupta discovered that on certain Intel processors, the Linux kernel did not properly perform invalidation on page table updates by virtual guest operating systems. A local attacker in a guest VM could use this to cause a denial of service (host system crash). (CVE-2018-12207)

It was discovered that the Intel i915 graphics chipsets could cause a system hang when userspace performed a read from GT memory mapped input output (MMIO) when the product is in certain low power states. A local attacker could use this to cause a denial of service. (CVE-2019-0154)

Hui Peng discovered that the Atheros AR6004 USB Wi-Fi device driver for the Linux kernel did not properly validate endpoint descriptors returned by the device. A physically proximate attacker could use this to cause a denial of service (system crash). (CVE-2019-15098)

Ori Nimron discovered that the AX25 network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17052)

Ori Nimron discovered that the IEEE 802.15.4 Low-Rate Wireless network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17053)

Ori Nimron discovered that the Appletalk network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17054)

Ori Nimron discovered that the modular ISDN network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17055)

Ori Nimron discovered that the Near field Communication (NFC) network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17056)

Nico Waisman discovered that a buffer overflow existed in the Realtek Wi-Fi driver for the Linux kernel when handling Notice of Absence frames. A physically proximate attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-17666)

Update instructions

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

Ubuntu 18.04 LTS
linux-image-4.15.0-1064-oem - 4.15.0-1064.73
linux-image-4.15.0-70-generic - 4.15.0-70.79
linux-image-4.15.0-70-generic-lpae - 4.15.0-70.79
linux-image-4.15.0-70-lowlatency - 4.15.0-70.79
linux-image-generic - 4.15.0.70.72
linux-image-generic-lpae - 4.15.0.70.72
linux-image-lowlatency - 4.15.0.70.72
linux-image-oem - 4.15.0.1064.68
linux-image-virtual - 4.15.0.70.72
Ubuntu 16.04 LTS
linux-image-4.15.0-70-generic - 4.15.0-70.79~16.04.1
linux-image-4.15.0-70-generic-lpae - 4.15.0-70.79~16.04.1
linux-image-4.15.0-70-lowlatency - 4.15.0-70.79~16.04.1
linux-image-generic-hwe-16.04 - 4.15.0.70.90
linux-image-generic-lpae-hwe-16.04 - 4.15.0.70.90
linux-image-lowlatency-hwe-16.04 - 4.15.0.70.90
linux-image-oem - 4.15.0.70.90
linux-image-virtual-hwe-16.04 - 4.15.0.70.90

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

Please note that mitigating the TSX (CVE-2019-11135) and i915 (CVE-2019-0154) issues requires corresponding microcode and graphics firmware updates respectively.

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
2019. november 13.

USN-4183-2: Linux kernel vulnerability

linux vulnerability

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

  • Ubuntu 19.10
Summary

Several security issues were fixed in the Linux kernel.

Software Description
  • linux - Linux kernel
Details

USN-4183-1 fixed vulnerabilities in the Linux kernel. It was discovered that the kernel fix for CVE-2019-0155 (i915 missing Blitter Command Streamer check) was incomplete on 64-bit Intel x86 systems. This update addresses the issue.

We apologize for the inconvenience.

Original advisory details:

Stephan van Schaik, Alyssa Milburn, Sebastian Österlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel processors using Transactional Synchronization Extensions (TSX) could expose memory contents previously stored in microarchitectural buffers to a malicious process that is executing on the same CPU core. A local attacker could use this to expose sensitive information. (CVE-2019-11135)

It was discovered that the Intel i915 graphics chipsets allowed userspace to modify page table entries via writes to MMIO from the Blitter Command Streamer and expose kernel memory information. A local attacker could use this to expose sensitive information or possibly elevate privileges. (CVE-2019-0155)

Deepak Gupta discovered that on certain Intel processors, the Linux kernel did not properly perform invalidation on page table updates by virtual guest operating systems. A local attacker in a guest VM could use this to cause a denial of service (host system crash). (CVE-2018-12207)

It was discovered that the Intel i915 graphics chipsets could cause a system hang when userspace performed a read from GT memory mapped input output (MMIO) when the product is in certain low power states. A local attacker could use this to cause a denial of service. (CVE-2019-0154)

Jann Horn discovered a reference count underflow in the shiftfs implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-15791)

Jann Horn discovered a type confusion vulnerability in the shiftfs implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-15792)

Jann Horn discovered that the shiftfs implementation in the Linux kernel did not use the correct file system uid/gid when the user namespace of a lower file system is not in the init user namespace. A local attacker could use this to possibly bypass DAC permissions or have some other unspecified impact. (CVE-2019-15793)

It was discovered that a buffer overflow existed in the 802.11 Wi-Fi configuration interface for the Linux kernel when handling beacon settings. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-16746)

Nico Waisman discovered that a buffer overflow existed in the Realtek Wi-Fi driver for the Linux kernel when handling Notice of Absence frames. A physically proximate attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-17666)

Update instructions

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

Ubuntu 19.10
linux-image-5.3.0-23-generic - 5.3.0-23.25
linux-image-5.3.0-23-generic-lpae - 5.3.0-23.25
linux-image-5.3.0-23-lowlatency - 5.3.0-23.25
linux-image-5.3.0-23-snapdragon - 5.3.0-23.25
linux-image-generic - 5.3.0.23.27
linux-image-generic-lpae - 5.3.0.23.27
linux-image-lowlatency - 5.3.0.23.27
linux-image-snapdragon - 5.3.0.23.27
linux-image-virtual - 5.3.0.23.27

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

Please note that mitigating the TSX (CVE-2019-11135) and i915 (CVE-2019-0154) issues requires corresponding microcode and graphics firmware updates respectively.

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
2019. november 13.

USN-4184-2: Linux kernel vulnerability and regression

linux, linux-hwe, linux-oem-osp1 vulnerability and regression

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

  • Ubuntu 19.04
  • Ubuntu 18.04 LTS
Summary

Several issues were fixed in the Linux kernel.

Software Description
  • linux - Linux kernel
  • linux-hwe - Linux hardware enablement (HWE) kernel
  • linux-oem-osp1 - Linux kernel for OEM processors
Details

USN-4184-1 fixed vulnerabilities in the Linux kernel. It was discovered that the kernel fix for CVE-2019-0155 (i915 missing Blitter Command Streamer check) was incomplete on 64-bit Intel x86 systems. Also, the update introduced a regression that broke KVM guests where extended page tables (EPT) are disabled or not supported. This update addresses both issues.

We apologize for the inconvenience.

Original advisory details:

Stephan van Schaik, Alyssa Milburn, Sebastian Österlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel processors using Transactional Synchronization Extensions (TSX) could expose memory contents previously stored in microarchitectural buffers to a malicious process that is executing on the same CPU core. A local attacker could use this to expose sensitive information. (CVE-2019-11135)

It was discovered that the Intel i915 graphics chipsets allowed userspace to modify page table entries via writes to MMIO from the Blitter Command Streamer and expose kernel memory information. A local attacker could use this to expose sensitive information or possibly elevate privileges. (CVE-2019-0155)

Deepak Gupta discovered that on certain Intel processors, the Linux kernel did not properly perform invalidation on page table updates by virtual guest operating systems. A local attacker in a guest VM could use this to cause a denial of service (host system crash). (CVE-2018-12207)

It was discovered that the Intel i915 graphics chipsets could cause a system hang when userspace performed a read from GT memory mapped input output (MMIO) when the product is in certain low power states. A local attacker could use this to cause a denial of service. (CVE-2019-0154)

Hui Peng discovered that the Atheros AR6004 USB Wi-Fi device driver for the Linux kernel did not properly validate endpoint descriptors returned by the device. A physically proximate attacker could use this to cause a denial of service (system crash). (CVE-2019-15098)

Jann Horn discovered a reference count underflow in the shiftfs implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-15791)

Jann Horn discovered a type confusion vulnerability in the shiftfs implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-15792)

Jann Horn discovered that the shiftfs implementation in the Linux kernel did not use the correct file system uid/gid when the user namespace of a lower file system is not in the init user namespace. A local attacker could use this to possibly bypass DAC permissions or have some other unspecified impact. (CVE-2019-15793)

Ori Nimron discovered that the AX25 network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17052)

Ori Nimron discovered that the IEEE 802.15.4 Low-Rate Wireless network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17053)

Ori Nimron discovered that the Appletalk network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17054)

Ori Nimron discovered that the modular ISDN network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17055)

Ori Nimron discovered that the Near field Communication (NFC) network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17056)

Nico Waisman discovered that a buffer overflow existed in the Realtek Wi-Fi driver for the Linux kernel when handling Notice of Absence frames. A physically proximate attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-17666)

Update instructions

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

Ubuntu 19.04
linux-image-5.0.0-36-generic - 5.0.0-36.39
linux-image-5.0.0-36-generic-lpae - 5.0.0-36.39
linux-image-5.0.0-36-lowlatency - 5.0.0-36.39
linux-image-generic - 5.0.0.36.38
linux-image-generic-lpae - 5.0.0.36.38
linux-image-lowlatency - 5.0.0.36.38
linux-image-virtual - 5.0.0.36.38
Ubuntu 18.04 LTS
linux-image-5.0.0-1028-oem-osp1 - 5.0.0-1028.32
linux-image-5.0.0-36-generic - 5.0.0-36.39~18.04.1
linux-image-5.0.0-36-generic-lpae - 5.0.0-36.39~18.04.1
linux-image-5.0.0-36-lowlatency - 5.0.0-36.39~18.04.1
linux-image-generic-hwe-18.04 - 5.0.0.36.94
linux-image-generic-lpae-hwe-18.04 - 5.0.0.36.94
linux-image-lowlatency-hwe-18.04 - 5.0.0.36.94
linux-image-oem-osp1 - 5.0.0.1028.32
linux-image-virtual-hwe-18.04 - 5.0.0.36.94

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

Please note that mitigating the TSX (CVE-2019-11135) and i915 (CVE-2019-0154) issues requires corresponding microcode and graphics firmware updates respectively.

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
2019. november 13.

USN-4190-1: libjpeg-turbo vulnerabilities

libjpeg-turbo vulnerabilities

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

  • Ubuntu 19.04
  • Ubuntu 18.04 LTS
  • Ubuntu 16.04 LTS
Summary

Several security issues were fixed in libjpeg-turbo.

Software Description
  • libjpeg-turbo - library for handling JPEG files
Details

It was discovered that libjpeg-turbo incorrectly handled certain BMP images. An attacker could possibly use this issue to expose sensitive information. This issue only affected Ubuntu 16.04 LTS and Ubuntu 18.04 LTS. (CVE-2018-14498)

It was discovered that libjpeg-turbo incorrectly handled certain JPEG images. An attacker could possibly use this issue to expose sensitive information. This issue only affected Ubuntu 19.04. (CVE-2018-19664)

It was discovered that libjpeg-turbo incorrectly handled certain BMP images. An attacker could possibly use this issue to execute arbitrary code. This issue only affected Ubuntu 19.04. (CVE-2018-20330)

It was discovered that libjpeg-turbo incorrectly handled certain JPEG images. An attacker could possibly cause a denial of service or execute arbitrary code. (CVE-2019-2201)

Update instructions

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

Ubuntu 19.04
libjpeg-turbo8 - 2.0.1-0ubuntu2.2
Ubuntu 18.04 LTS
libjpeg-turbo8 - 1.5.2-0ubuntu5.18.04.3
Ubuntu 16.04 LTS
libjpeg-turbo8 - 1.4.2-0ubuntu3.3

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

In general, a standard system update will make all the necessary changes.

References
2019. november 13.

USN-4189-1: DPDK vulnerability

dpdk vulnerability

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

  • Ubuntu 19.10
  • Ubuntu 19.04
  • Ubuntu 18.04 LTS
Summary

DPDK could be made to consume resources if it received specially crafted input.

Software Description
  • dpdk - set of libraries for fast packet processing
Details

Jason Wang discovered that DPDK incorrectly handled certain messages. An attacker in a malicious container could possibly use this issue to cause DPDK to leak resources, resulting in a denial of service.

Update instructions

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

Ubuntu 19.10
dpdk - 18.11.4-1ubuntu0.19.10.1
Ubuntu 19.04
dpdk - 18.11.4-1ubuntu0.19.04.1
Ubuntu 18.04 LTS
dpdk - 17.11.8-0~ubuntu18.04.2

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

This update uses a new upstream release, which includes additional bug fixes. In general, a standard system update will make all the necessary changes.

References
2019. november 13.

USN-4188-1: Linux kernel vulnerability

linux, linux-lts-trusty vulnerability

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

  • Ubuntu 12.04 ESM
Summary

The system could be made to expose sensitive information.

Software Description
  • linux - Linux kernel
  • linux-lts-trusty - Linux hardware enablement kernel from Trusty for Precise ESM
Details

Stephan van Schaik, Alyssa Milburn, Sebastian Österlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel processors using Transactional Synchronization Extensions (TSX) could expose memory contents previously stored in microarchitectural buffers to a malicious process that is executing on the same CPU core. A local attacker could use this to expose sensitive information.

Update instructions

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

Ubuntu 12.04 ESM
linux-image-3.13.0-175-generic - 3.13.0-175.226~12.04.1
linux-image-3.13.0-175-generic-lpae - 3.13.0-175.226~12.04.1
linux-image-3.13.0-175-lowlatency - 3.13.0-175.226~12.04.1
linux-image-3.2.0-144-generic - 3.2.0-144.191
linux-image-3.2.0-144-generic-pae - 3.2.0-144.191
linux-image-3.2.0-144-virtual - 3.2.0-144.191
linux-image-generic - 3.2.0.144.159
linux-image-generic-lpae-lts-trusty - 3.13.0.175.163
linux-image-generic-lts-trusty - 3.13.0.175.163
linux-image-generic-pae - 3.2.0.144.159
linux-image-server - 3.2.0.144.159
linux-image-virtual - 3.2.0.144.159

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

Please note that mitigating the TSX (CVE-2019-11135) issue requires a corresponding Intel processor microcode update.

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
2019. november 13.

USN-4185-2: Linux kernel (Azure) vulnerabilities

linux-azure vulnerabilities

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

  • Ubuntu 14.04 ESM
Summary

Several security issues were fixed in the Linux kernel.

Software Description
  • linux-azure - Linux kernel for Microsoft Azure Cloud systems
Details

Stephan van Schaik, Alyssa Milburn, Sebastian Österlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel processors using Transactional Synchronization Extensions (TSX) could expose memory contents previously stored in microarchitectural buffers to a malicious process that is executing on the same CPU core. A local attacker could use this to expose sensitive information. (CVE-2019-11135)

Deepak Gupta discovered that on certain Intel processors, the Linux kernel did not properly perform invalidation on page table updates by virtual guest operating systems. A local attacker in a guest VM could use this to cause a denial of service (host system crash). (CVE-2018-12207)

Ori Nimron discovered that the AX25 network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17052)

Ori Nimron discovered that the IEEE 802.15.4 Low-Rate Wireless network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17053)

Ori Nimron discovered that the Appletalk network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17054)

Ori Nimron discovered that the modular ISDN network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17055)

Ori Nimron discovered that the Near field Communication (NFC) network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17056)

Update instructions

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

Ubuntu 14.04 ESM
linux-image-4.15.0-1063-azure - 4.15.0-1063.68~14.04.1
linux-image-azure - 4.15.0.1063.49

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

Please note that mitigating the TSX (CVE-2019-11135) issue requires a corresponding Intel processor microcode update.

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
2019. november 13.

USN-4187-1: Linux kernel vulnerability

linux vulnerability

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

  • Ubuntu 14.04 ESM
Summary

The system could be made to expose sensitive information.

Software Description
  • linux - Linux kernel
Details

Stephan van Schaik, Alyssa Milburn, Sebastian Österlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel processors using Transactional Synchronization Extensions (TSX) could expose memory contents previously stored in microarchitectural buffers to a malicious process that is executing on the same CPU core. A local attacker could use this to expose sensitive information.

Update instructions

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

Ubuntu 14.04 ESM
linux-image-3.13.0-175-generic - 3.13.0-175.226
linux-image-3.13.0-175-generic-lpae - 3.13.0-175.226
linux-image-3.13.0-175-lowlatency - 3.13.0-175.226
linux-image-generic - 3.13.0.175.186
linux-image-generic-lpae - 3.13.0.175.186
linux-image-lowlatency - 3.13.0.175.186
linux-image-server - 3.13.0.175.186
linux-image-virtual - 3.13.0.175.186

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

Please note that mitigating the TSX (CVE-2019-11135) issue requires a corresponding Intel processor microcode update.

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
2019. november 13.

USN-4186-2: Linux kernel (Xenial HWE) vulnerabilities

linux-lts-xenial, linux-aws vulnerabilities

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

  • Ubuntu 14.04 ESM
Summary

Several security issues were fixed in the Linux kernel.

Software Description
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-lts-xenial - Linux hardware enablement kernel from Xenial for Trusty
Details

USN-4186-1 fixed vulnerabilities in the Linux kernel for Ubuntu 16.04 LTS. This update provides the corresponding updates for the Linux Hardware Enablement (HWE) kernel from Ubuntu 16.04 LTS for Ubuntu 14.04 ESM.

Stephan van Schaik, Alyssa Milburn, Sebastian Österlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel processors using Transactional Synchronization Extensions (TSX) could expose memory contents previously stored in microarchitectural buffers to a malicious process that is executing on the same CPU core. A local attacker could use this to expose sensitive information. (CVE-2019-11135)

It was discovered that the Intel i915 graphics chipsets allowed userspace to modify page table entries via writes to MMIO from the Blitter Command Streamer and expose kernel memory information. A local attacker could use this to expose sensitive information or possibly elevate privileges. (CVE-2019-0155)

Deepak Gupta discovered that on certain Intel processors, the Linux kernel did not properly perform invalidation on page table updates by virtual guest operating systems. A local attacker in a guest VM could use this to cause a denial of service (host system crash). (CVE-2018-12207)

It was discovered that the Intel i915 graphics chipsets could cause a system hang when userspace performed a read from GT memory mapped input output (MMIO) when the product is in certain low power states. A local attacker could use this to cause a denial of service. (CVE-2019-0154)

Hui Peng discovered that the Atheros AR6004 USB Wi-Fi device driver for the Linux kernel did not properly validate endpoint descriptors returned by the device. A physically proximate attacker could use this to cause a denial of service (system crash). (CVE-2019-15098)

Ori Nimron discovered that the AX25 network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17052)

Ori Nimron discovered that the IEEE 802.15.4 Low-Rate Wireless network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17053)

Ori Nimron discovered that the Appletalk network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17054)

Ori Nimron discovered that the modular ISDN network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17055)

Ori Nimron discovered that the Near field Communication (NFC) network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17056)

Nico Waisman discovered that a buffer overflow existed in the Realtek Wi-Fi driver for the Linux kernel when handling Notice of Absence frames. A physically proximate attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-17666)

Update instructions

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

Ubuntu 14.04 ESM
linux-image-4.4.0-1058-aws - 4.4.0-1058.62
linux-image-4.4.0-168-generic - 4.4.0-168.197~14.04.1
linux-image-4.4.0-168-generic-lpae - 4.4.0-168.197~14.04.1
linux-image-4.4.0-168-lowlatency - 4.4.0-168.197~14.04.1
linux-image-4.4.0-168-powerpc-e500mc - 4.4.0-168.197~14.04.1
linux-image-4.4.0-168-powerpc-smp - 4.4.0-168.197~14.04.1
linux-image-4.4.0-168-powerpc64-emb - 4.4.0-168.197~14.04.1
linux-image-4.4.0-168-powerpc64-smp - 4.4.0-168.197~14.04.1
linux-image-aws - 4.4.0.1058.59
linux-image-generic-lpae-lts-xenial - 4.4.0.168.147
linux-image-generic-lts-xenial - 4.4.0.168.147
linux-image-lowlatency-lts-xenial - 4.4.0.168.147
linux-image-powerpc-e500mc-lts-xenial - 4.4.0.168.147
linux-image-powerpc-smp-lts-xenial - 4.4.0.168.147
linux-image-powerpc64-emb-lts-xenial - 4.4.0.168.147
linux-image-powerpc64-smp-lts-xenial - 4.4.0.168.147
linux-image-virtual-lts-xenial - 4.4.0.168.147

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

Please note that mitigating the TSX (CVE-2019-11135) and i915 (CVE-2019-0154) issues requires corresponding microcode and graphics firmware updates respectively.

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
2019. november 13.

USN-4186-1: Linux kernel vulnerabilities

linux, linux-aws, linux-kvm 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
Details

Stephan van Schaik, Alyssa Milburn, Sebastian Österlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel processors using Transactional Synchronization Extensions (TSX) could expose memory contents previously stored in microarchitectural buffers to a malicious process that is executing on the same CPU core. A local attacker could use this to expose sensitive information. (CVE-2019-11135)

It was discovered that the Intel i915 graphics chipsets allowed userspace to modify page table entries via writes to MMIO from the Blitter Command Streamer and expose kernel memory information. A local attacker could use this to expose sensitive information or possibly elevate privileges. (CVE-2019-0155)

Deepak Gupta discovered that on certain Intel processors, the Linux kernel did not properly perform invalidation on page table updates by virtual guest operating systems. A local attacker in a guest VM could use this to cause a denial of service (host system crash). (CVE-2018-12207)

It was discovered that the Intel i915 graphics chipsets could cause a system hang when userspace performed a read from GT memory mapped input output (MMIO) when the product is in certain low power states. A local attacker could use this to cause a denial of service. (CVE-2019-0154)

Hui Peng discovered that the Atheros AR6004 USB Wi-Fi device driver for the Linux kernel did not properly validate endpoint descriptors returned by the device. A physically proximate attacker could use this to cause a denial of service (system crash). (CVE-2019-15098)

It was discovered that a buffer overflow existed in the 802.11 Wi-Fi configuration interface for the Linux kernel when handling beacon settings. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-16746)

Ori Nimron discovered that the AX25 network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17052)

Ori Nimron discovered that the IEEE 802.15.4 Low-Rate Wireless network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17053)

Ori Nimron discovered that the Appletalk network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17054)

Ori Nimron discovered that the modular ISDN network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17055)

Ori Nimron discovered that the Near field Communication (NFC) network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17056)

Nico Waisman discovered that a buffer overflow existed in the Realtek Wi-Fi driver for the Linux kernel when handling Notice of Absence frames. A physically proximate attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-17666)

Maddie Stone discovered that the Binder IPC Driver implementation in the Linux kernel contained a use-after-free vulnerability. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-2215)

Update instructions

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

Ubuntu 16.04 LTS
linux-image-4.4.0-1062-kvm - 4.4.0-1062.69
linux-image-4.4.0-1098-aws - 4.4.0-1098.109
linux-image-4.4.0-168-generic - 4.4.0-168.197
linux-image-4.4.0-168-generic-lpae - 4.4.0-168.197
linux-image-4.4.0-168-lowlatency - 4.4.0-168.197
linux-image-4.4.0-168-powerpc-e500mc - 4.4.0-168.197
linux-image-4.4.0-168-powerpc-smp - 4.4.0-168.197
linux-image-4.4.0-168-powerpc64-emb - 4.4.0-168.197
linux-image-4.4.0-168-powerpc64-smp - 4.4.0-168.197
linux-image-aws - 4.4.0.1098.102
linux-image-generic - 4.4.0.168.176
linux-image-generic-lpae - 4.4.0.168.176
linux-image-kvm - 4.4.0.1062.62
linux-image-lowlatency - 4.4.0.168.176
linux-image-powerpc-e500mc - 4.4.0.168.176
linux-image-powerpc-smp - 4.4.0.168.176
linux-image-powerpc64-emb - 4.4.0.168.176
linux-image-powerpc64-smp - 4.4.0.168.176
linux-image-virtual - 4.4.0.168.176

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

Please note that mitigating the TSX (CVE-2019-11135) and i915 (CVE-2019-0154) issues requires corresponding microcode and graphics firmware updates respectively.

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
2019. november 13.

USN-4185-1: Linux kernel vulnerabilities

linux, linux-aws, linux-aws-hwe, linux-azure, linux-gcp, linux-gke-4.15, linux-hwe, linux-kvm, linux-oem, linux-oracle vulnerabilities

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

  • Ubuntu 18.04 LTS
  • 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-gke-4.15 - Linux kernel for Google Container Engine (GKE) systems
  • linux-kvm - Linux kernel for cloud environments
  • linux-oem - Linux kernel for OEM processors
  • linux-oracle - Linux kernel for Oracle Cloud systems
  • linux-aws-hwe - Linux kernel for Amazon Web Services (AWS-HWE) systems
  • linux-azure - Linux kernel for Microsoft Azure Cloud systems
  • linux-gcp - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-hwe - Linux hardware enablement (HWE) kernel
Details

Stephan van Schaik, Alyssa Milburn, Sebastian Österlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel processors using Transactional Synchronization Extensions (TSX) could expose memory contents previously stored in microarchitectural buffers to a malicious process that is executing on the same CPU core. A local attacker could use this to expose sensitive information. (CVE-2019-11135)

It was discovered that the Intel i915 graphics chipsets allowed userspace to modify page table entries via writes to MMIO from the Blitter Command Streamer and expose kernel memory information. A local attacker could use this to expose sensitive information or possibly elevate privileges. (CVE-2019-0155)

Deepak Gupta discovered that on certain Intel processors, the Linux kernel did not properly perform invalidation on page table updates by virtual guest operating systems. A local attacker in a guest VM could use this to cause a denial of service (host system crash). (CVE-2018-12207)

It was discovered that the Intel i915 graphics chipsets could cause a system hang when userspace performed a read from GT memory mapped input output (MMIO) when the product is in certain low power states. A local attacker could use this to cause a denial of service. (CVE-2019-0154)

Hui Peng discovered that the Atheros AR6004 USB Wi-Fi device driver for the Linux kernel did not properly validate endpoint descriptors returned by the device. A physically proximate attacker could use this to cause a denial of service (system crash). (CVE-2019-15098)

Ori Nimron discovered that the AX25 network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17052)

Ori Nimron discovered that the IEEE 802.15.4 Low-Rate Wireless network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17053)

Ori Nimron discovered that the Appletalk network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17054)

Ori Nimron discovered that the modular ISDN network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17055)

Ori Nimron discovered that the Near field Communication (NFC) network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17056)

Nico Waisman discovered that a buffer overflow existed in the Realtek Wi-Fi driver for the Linux kernel when handling Notice of Absence frames. A physically proximate attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-17666)

Update instructions

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

Ubuntu 18.04 LTS
linux-image-4.15.0-1029-oracle - 4.15.0-1029.32
linux-image-4.15.0-1048-gke - 4.15.0-1048.51
linux-image-4.15.0-1050-kvm - 4.15.0-1050.50
linux-image-4.15.0-1054-aws - 4.15.0-1054.56
linux-image-4.15.0-1063-oem - 4.15.0-1063.72
linux-image-4.15.0-69-generic - 4.15.0-69.78
linux-image-4.15.0-69-generic-lpae - 4.15.0-69.78
linux-image-4.15.0-69-lowlatency - 4.15.0-69.78
linux-image-aws - 4.15.0.1054.55
linux-image-aws-lts-18.04 - 4.15.0.1054.55
linux-image-generic - 4.15.0.69.71
linux-image-generic-lpae - 4.15.0.69.71
linux-image-gke - 4.15.0.1048.51
linux-image-gke-4.15 - 4.15.0.1048.51
linux-image-kvm - 4.15.0.1050.50
linux-image-lowlatency - 4.15.0.69.71
linux-image-oem - 4.15.0.1063.67
linux-image-oracle - 4.15.0.1029.34
linux-image-oracle-lts-18.04 - 4.15.0.1029.34
linux-image-powerpc-e500mc - 4.15.0.69.71
linux-image-powerpc-smp - 4.15.0.69.71
linux-image-powerpc64-emb - 4.15.0.69.71
linux-image-powerpc64-smp - 4.15.0.69.71
linux-image-virtual - 4.15.0.69.71
Ubuntu 16.04 LTS
linux-image-4.15.0-1029-oracle - 4.15.0-1029.32~16.04.1
linux-image-4.15.0-1049-gcp - 4.15.0-1049.52
linux-image-4.15.0-1054-aws - 4.15.0-1054.56~16.04.1
linux-image-4.15.0-1063-azure - 4.15.0-1063.68
linux-image-4.15.0-69-generic - 4.15.0-69.78~16.04.1
linux-image-4.15.0-69-generic-lpae - 4.15.0-69.78~16.04.1
linux-image-4.15.0-69-lowlatency - 4.15.0-69.78~16.04.1
linux-image-aws-hwe - 4.15.0.1054.54
linux-image-azure - 4.15.0.1063.66
linux-image-gcp - 4.15.0.1049.63
linux-image-generic-hwe-16.04 - 4.15.0.69.89
linux-image-generic-lpae-hwe-16.04 - 4.15.0.69.89
linux-image-gke - 4.15.0.1049.63
linux-image-lowlatency-hwe-16.04 - 4.15.0.69.89
linux-image-oem - 4.15.0.69.89
linux-image-oracle - 4.15.0.1029.22
linux-image-virtual-hwe-16.04 - 4.15.0.69.89

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

Please note that mitigating the TSX (CVE-2019-11135) and i915 (CVE-2019-0154) issues requires corresponding microcode and graphics firmware updates respectively.

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
2019. november 13.

USN-4184-1: Linux kernel vulnerabilities

linux, linux-aws, linux-azure, linux-gcp, linux-gke-5.0, linux-hwe, linux-kvm, linux-oem-osp1, linux-oracle, linux-raspi2 vulnerabilities

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

  • Ubuntu 19.04
  • Ubuntu 18.04 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-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-oracle - Linux kernel for Oracle Cloud systems
  • linux-raspi2 - Linux kernel for Raspberry Pi 2
  • linux-gke-5.0 - Linux kernel for Google Container Engine (GKE) systems
  • linux-hwe - Linux hardware enablement (HWE) kernel
  • linux-oem-osp1 - Linux kernel for OEM processors
Details

Stephan van Schaik, Alyssa Milburn, Sebastian Österlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel processors using Transactional Synchronization Extensions (TSX) could expose memory contents previously stored in microarchitectural buffers to a malicious process that is executing on the same CPU core. A local attacker could use this to expose sensitive information. (CVE-2019-11135)

It was discovered that the Intel i915 graphics chipsets allowed userspace to modify page table entries via writes to MMIO from the Blitter Command Streamer and expose kernel memory information. A local attacker could use this to expose sensitive information or possibly elevate privileges. (CVE-2019-0155)

Deepak Gupta discovered that on certain Intel processors, the Linux kernel did not properly perform invalidation on page table updates by virtual guest operating systems. A local attacker in a guest VM could use this to cause a denial of service (host system crash). (CVE-2018-12207)

It was discovered that the Intel i915 graphics chipsets could cause a system hang when userspace performed a read from GT memory mapped input output (MMIO) when the product is in certain low power states. A local attacker could use this to cause a denial of service. (CVE-2019-0154)

Hui Peng discovered that the Atheros AR6004 USB Wi-Fi device driver for the Linux kernel did not properly validate endpoint descriptors returned by the device. A physically proximate attacker could use this to cause a denial of service (system crash). (CVE-2019-15098)

Jann Horn discovered a reference count underflow in the shiftfs implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-15791)

Jann Horn discovered a type confusion vulnerability in the shiftfs implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-15792)

Jann Horn discovered that the shiftfs implementation in the Linux kernel did not use the correct file system uid/gid when the user namespace of a lower file system is not in the init user namespace. A local attacker could use this to possibly bypass DAC permissions or have some other unspecified impact. (CVE-2019-15793)

Ori Nimron discovered that the AX25 network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17052)

Ori Nimron discovered that the IEEE 802.15.4 Low-Rate Wireless network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17053)

Ori Nimron discovered that the Appletalk network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17054)

Ori Nimron discovered that the modular ISDN network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17055)

Ori Nimron discovered that the Near field Communication (NFC) network protocol implementation in the Linux kernel did not properly perform permissions checks. A local attacker could use this to create a raw socket. (CVE-2019-17056)

Nico Waisman discovered that a buffer overflow existed in the Realtek Wi-Fi driver for the Linux kernel when handling Notice of Absence frames. A physically proximate attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-17666)

Update instructions

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

Ubuntu 19.04
linux-image-5.0.0-1007-oracle - 5.0.0-1007.12
linux-image-5.0.0-1021-aws - 5.0.0-1021.24
linux-image-5.0.0-1022-kvm - 5.0.0-1022.24
linux-image-5.0.0-1022-raspi2 - 5.0.0-1022.23
linux-image-5.0.0-1025-azure - 5.0.0-1025.27
linux-image-5.0.0-1025-gcp - 5.0.0-1025.26
linux-image-5.0.0-35-generic - 5.0.0-35.38
linux-image-5.0.0-35-generic-lpae - 5.0.0-35.38
linux-image-5.0.0-35-lowlatency - 5.0.0-35.38
linux-image-aws - 5.0.0.1021.23
linux-image-azure - 5.0.0.1025.25
linux-image-gcp - 5.0.0.1025.50
linux-image-generic - 5.0.0.35.37
linux-image-generic-lpae - 5.0.0.35.37
linux-image-gke - 5.0.0.1025.50
linux-image-kvm - 5.0.0.1022.23
linux-image-lowlatency - 5.0.0.35.37
linux-image-oracle - 5.0.0.1007.33
linux-image-raspi2 - 5.0.0.1022.20
linux-image-virtual - 5.0.0.35.37
Ubuntu 18.04 LTS
linux-image-5.0.0-1025-azure - 5.0.0-1025.27~18.04.1
linux-image-5.0.0-1025-gcp - 5.0.0-1025.26~18.04.1
linux-image-5.0.0-1025-gke - 5.0.0-1025.26~18.04.1
linux-image-5.0.0-1027-oem-osp1 - 5.0.0-1027.31
linux-image-5.0.0-35-generic - 5.0.0-35.38~18.04.1
linux-image-5.0.0-35-generic-lpae - 5.0.0-35.38~18.04.1
linux-image-5.0.0-35-lowlatency - 5.0.0-35.38~18.04.1
linux-image-azure - 5.0.0.1025.36
linux-image-gcp - 5.0.0.1025.29
linux-image-generic-hwe-18.04 - 5.0.0.35.93
linux-image-generic-lpae-hwe-18.04 - 5.0.0.35.93
linux-image-gke-5.0 - 5.0.0.1025.14
linux-image-lowlatency-hwe-18.04 - 5.0.0.35.93
linux-image-oem-osp1 - 5.0.0.1027.31
linux-image-snapdragon-hwe-18.04 - 5.0.0.35.93
linux-image-virtual-hwe-18.04 - 5.0.0.35.93

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

Please note that mitigating the TSX (CVE-2019-11135) and i915 (CVE-2019-0154) issues requires corresponding microcode and graphics firmware updates respectively.

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
2019. november 13.

USN-4183-1: Linux kernel vulnerabilities

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

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

  • Ubuntu 19.10
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-oracle - Linux kernel for Oracle Cloud systems
  • linux-raspi2 - Linux kernel for Raspberry Pi 2
Details

Stephan van Schaik, Alyssa Milburn, Sebastian Österlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel processors using Transactional Synchronization Extensions (TSX) could expose memory contents previously stored in microarchitectural buffers to a malicious process that is executing on the same CPU core. A local attacker could use this to expose sensitive information. (CVE-2019-11135)

It was discovered that the Intel i915 graphics chipsets allowed userspace to modify page table entries via writes to MMIO from the Blitter Command Streamer and expose kernel memory information. A local attacker could use this to expose sensitive information or possibly elevate privileges. (CVE-2019-0155)

Deepak Gupta discovered that on certain Intel processors, the Linux kernel did not properly perform invalidation on page table updates by virtual guest operating systems. A local attacker in a guest VM could use this to cause a denial of service (host system crash). (CVE-2018-12207)

It was discovered that the Intel i915 graphics chipsets could cause a system hang when userspace performed a read from GT memory mapped input output (MMIO) when the product is in certain low power states. A local attacker could use this to cause a denial of service. (CVE-2019-0154)

Jann Horn discovered a reference count underflow in the shiftfs implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-15791)

Jann Horn discovered a type confusion vulnerability in the shiftfs implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-15792)

Jann Horn discovered that the shiftfs implementation in the Linux kernel did not use the correct file system uid/gid when the user namespace of a lower file system is not in the init user namespace. A local attacker could use this to possibly bypass DAC permissions or have some other unspecified impact. (CVE-2019-15793)

It was discovered that a buffer overflow existed in the 802.11 Wi-Fi configuration interface for the Linux kernel when handling beacon settings. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-16746)

Nico Waisman discovered that a buffer overflow existed in the Realtek Wi-Fi driver for the Linux kernel when handling Notice of Absence frames. A physically proximate attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-17666)

Update instructions

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

Ubuntu 19.10
linux-image-5.3.0-1006-oracle - 5.3.0-1006.7
linux-image-5.3.0-1007-aws - 5.3.0-1007.8
linux-image-5.3.0-1007-azure - 5.3.0-1007.8
linux-image-5.3.0-1007-kvm - 5.3.0-1007.8
linux-image-5.3.0-1008-gcp - 5.3.0-1008.9
linux-image-5.3.0-1012-raspi2 - 5.3.0-1012.14
linux-image-5.3.0-22-generic - 5.3.0-22.24
linux-image-5.3.0-22-generic-lpae - 5.3.0-22.24
linux-image-5.3.0-22-lowlatency - 5.3.0-22.24
linux-image-5.3.0-22-snapdragon - 5.3.0-22.24
linux-image-aws - 5.3.0.1007.9
linux-image-azure - 5.3.0.1007.25
linux-image-gcp - 5.3.0.1008.9
linux-image-generic - 5.3.0.22.26
linux-image-generic-lpae - 5.3.0.22.26
linux-image-gke - 5.3.0.1008.9
linux-image-kvm - 5.3.0.1007.9
linux-image-lowlatency - 5.3.0.22.26
linux-image-oracle - 5.3.0.1006.7
linux-image-raspi2 - 5.3.0.1012.9
linux-image-snapdragon - 5.3.0.22.26
linux-image-virtual - 5.3.0.22.26

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

Please note that mitigating the TSX (CVE-2019-11135) and i915 (CVE-2019-0154) issues requires corresponding microcode and graphics firmware updates respectively.

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
2019. november 12.

USN-4182-2: Intel Microcode update

intel-microcode update

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

  • Ubuntu 14.04 ESM
Summary

Several security issues were fixed in Intel Microcode.

Software Description
  • intel-microcode - Processor microcode for Intel CPUs
Details

USN-4182-2 provided updates for Intel Microcode. This update provides the corresponding update for Ubuntu 14.04 ESM.

Stephan van Schaik, Alyssa Milburn, Sebastian Österlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Giorgi Maisuradze, Moritz Lipp, Michael Schwarz, Daniel Gruss, and Jo Van Bulck discovered that Intel processors using Transactional Synchronization Extensions (TSX) could expose memory contents previously stored in microarchitectural buffers to a malicious process that is executing on the same CPU core. A local attacker could use this to expose sensitive information. (CVE-2019-11135)

It was discovered that certain Intel Xeon processors did not properly restrict access to a voltage modulation interface. A local privileged attacker could use this to cause a denial of service (system crash). (CVE-2019-11139)

Update instructions

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

Ubuntu 14.04 ESM
intel-microcode - 3.20191112-0ubuntu0.14.04.2

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. Please note that in order to fully mitigate CVE-2019-11139, a warm reboot is required after applying the microcode update; so in effect a second reboot.

References