The following updates has been released for Ubuntu Linux:

LSN-0029-1: Linux kernel vulnerability
USN-3407-1: PyJWT vulnerability

LSN-0029-1: Linux kernel vulnerability

==========================================================================
Kernel Live Patch Security Notice LSN-0029-1
August 30, 2017

linux vulnerability
==========================================================================

A security issue affects these releases of Ubuntu:

| Series | Base kernel | Arch | flavors |
|------------------+--------------+----------+------------------|
| Ubuntu 14.04 LTS | 4.4.0 | amd64 | generic |
| Ubuntu 14.04 LTS | 4.4.0 | amd64 | lowlatency |
| Ubuntu 16.04 LTS | 4.4.0 | amd64 | generic |
| Ubuntu 16.04 LTS | 4.4.0 | amd64 | lowlatency |

Summary:

Several security issues were fixed in the kernel.

Software Description:
- linux: Linux kernel

Details:

It was discovered that the Linux kernel did not honor the UEFI secure boot
mode when performing a kexec operation. A local attacker could use this to
bypass secure boot restrictions. (CVE-2015-7837)

Huang Weller discovered that the ext4 filesystem implementation in the
Linux kernel mishandled a needs-flushing-before-commit list. A local
attacker could use this to expose sensitive information. (CVE-2017-7495)

Update instructions:

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

| Kernel | Version | flavors |
|-----------------+----------+--------------------------|
| 4.4.0-21.37 | 29.1 | generic, lowlatency |
| 4.4.0-22.39 | 29.1 | generic, lowlatency |
| 4.4.0-22.40 | 29.1 | generic, lowlatency |
| 4.4.0-24.43 | 29.1 | generic, lowlatency |
| 4.4.0-28.47 | 29.1 | generic, lowlatency |
| 4.4.0-31.50 | 29.1 | generic, lowlatency |
| 4.4.0-34.53 | 29.1 | generic, lowlatency |
| 4.4.0-36.55 | 29.1 | generic, lowlatency |
| 4.4.0-38.57 | 29.1 | generic, lowlatency |
| 4.4.0-42.62 | 29.1 | generic, lowlatency |
| 4.4.0-43.63 | 29.1 | generic, lowlatency |
| 4.4.0-45.66 | 29.1 | generic, lowlatency |
| 4.4.0-47.68 | 29.1 | generic, lowlatency |
| 4.4.0-51.72 | 29.1 | generic, lowlatency |
| 4.4.0-53.74 | 29.1 | generic, lowlatency |
| 4.4.0-57.78 | 29.1 | generic, lowlatency |
| 4.4.0-59.80 | 29.1 | generic, lowlatency |
| 4.4.0-62.83 | 29.1 | generic, lowlatency |
| 4.4.0-63.84 | 29.1 | generic, lowlatency |
| 4.4.0-64.85 | 29.1 | generic, lowlatency |
| 4.4.0-66.87 | 29.1 | generic, lowlatency |
| 4.4.0-67.88 | 29.1 | generic, lowlatency |
| 4.4.0-70.91 | 29.1 | generic, lowlatency |
| 4.4.0-71.92 | 29.1 | generic, lowlatency |
| 4.4.0-72.93 | 29.1 | generic, lowlatency |
| 4.4.0-75.96 | 29.1 | generic, lowlatency |
| 4.4.0-77.98 | 29.1 | generic, lowlatency |
| 4.4.0-78.99 | 29.1 | generic, lowlatency |
| 4.4.0-79.100 | 29.1 | generic, lowlatency |
| 4.4.0-81.104 | 29.1 | generic, lowlatency |
| 4.4.0-83.106 | 29.1 | generic, lowlatency |
| 4.4.0-87.110 | 29.1 | generic, lowlatency |
| 4.4.0-89.112 | 29.1 | generic, lowlatency |
| 4.4.0-91.114 | 29.1 | generic, lowlatency |
| lts-4.4.0-21.37_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-22.39_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-24.43_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-28.47_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-31.50_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-34.53_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-36.55_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-38.57_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-42.62_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-45.66_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-47.68_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-51.72_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-53.74_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-57.78_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-59.80_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-62.83_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-63.84_14.04.2-lts-xenial | 14.04.2 | generic, lowlatency |
| lts-4.4.0-64.85_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-66.87_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-70.91_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-71.92_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-72.93_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-75.96_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-78.99_14.04.2-lts-xenial | 14.04.2 | generic, lowlatency |
| lts-4.4.0-79.100_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-81.104_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |
| lts-4.4.0-87.110_14.04.1-lts-xenial | 14.04.1 | generic, lowlatency |

Additionally, you should install an updated kernel with these fixes and
reboot at your convienience.

References:
CVE-2015-7837, CVE-2017-7495

USN-3407-1: PyJWT vulnerability

==========================================================================
Ubuntu Security Notice USN-3407-1
August 30, 2017

pyjwt vulnerability
==========================================================================

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

- Ubuntu 17.04
- Ubuntu 16.04 LTS

Summary:

PyJWT could be made to crash if it received specially crafted
input.

Software Description:
- pyjwt: Python implementation of JSON Web Token

Details:

It was discovered that a vulnerability in PyJWT doesn't check
invalid_strings properly for some public keys. A remote attacker
could take advantage of a key confusion to craft JWTs from scratch.

Update instructions:

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

Ubuntu 17.04:
  python-jwt 1.4.2-1ubuntu0.1
  python3-jwt 1.4.2-1ubuntu0.1

Ubuntu 16.04 LTS:
  python-jwt 1.3.0-1ubuntu0.1
  python3-jwt 1.3.0-1ubuntu0.1

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

References:
  https://www.ubuntu.com/usn/usn-3407-1
  CVE-2017-11424

Package Information:
  https://launchpad.net/ubuntu/+source/pyjwt/1.4.2-1ubuntu0.1
  https://launchpad.net/ubuntu/+source/pyjwt/1.3.0-1ubuntu0.1