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Ubuntu Security Notice USN-4185-2
November 13, 2019

linux-azure vulnerabilities
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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

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:
  https://usn.ubuntu.com/4185-2
  https://usn.ubuntu.com/4185-1
  CVE-2018-12207, CVE-2019-11135, CVE-2019-17052, CVE-2019-17053,
  CVE-2019-17054, CVE-2019-17055, CVE-2019-17056,
  https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/TAA_MCEPSC_i915