ESB-2017.3031 - [Ubuntu] kernel: Multiple vulnerabilities 2017-11-30

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             AUSCERT External Security Bulletin Redistribution

               Kernel Live Patch Security Notice LSN-0032-2
                             30 November 2017


        AusCERT Security Bulletin Summary

Product:          kernel
Publisher:        Ubuntu
Operating System: Ubuntu
Impact/Access:    Denial of Service        -- Existing Account
                  Access Confidential Data -- Existing Account
Resolution:       Patch/Upgrade
CVE Names:        CVE-2017-14140 CVE-2017-12154 CVE-2017-12153

Reference:        ESB-2017.2807

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Kernel Live Patch Security Notice LSN-0032-2
November 23, 2017

linux vulnerability

A security issue affects these releases of Ubuntu:

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


Several security issues were fixed in the kernel.

Software Description:
- - linux: Linux kernel


Anthony Perard discovered that the Xen virtual block driver did not
properly initialize some data structures before passing them to user space.
A local attacker in a guest VM could use this to expose sensitive
information from the host OS or other guest VMs. (CVE-2017-10911)

Bo Zhang discovered that the netlink wireless configuration interface in
the Linux kernel did not properly validate attributes when handling certain
requests. A local attacker with the CAP_NET_ADMIN could use this to cause a
denial of service (system crash). (CVE-2017-12153)

It was discovered that the nested KVM implementation in the Linux kernel in
some situations did not properly prevent second level guests from reading
and writing the hardware CR8 register. A local attacker in a guest could
use this to cause a denial of service (system crash). (CVE-2017-12154)

Otto Ebeling discovered that the memory manager in the Linux kernel did not
properly check the effective UID in some situations. A local attacker could
use this to expose sensitive information. (CVE-2017-14140)

Update instructions:

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

| Kernel                              | Version  | flavors                  |
| 4.4.0-97.120                        | 32.2     | generic, lowlatency      |
| lts-4.4.0-67.88_14.04.1-lts-xenial  | 14.04.1  | generic, lowlatency      |
| lts-4.4.0-83.106_14.04.1-lts-xenial | 14.04.1  | generic, lowlatency      |
| lts-4.4.0-93.116_14.04.1-lts-xenial | 14.04.1  | generic, lowlatency      |
| lts-4.4.0-97.120_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.

  CVE-2017-10911, CVE-2017-12153, CVE-2017-12154, CVE-2017-14140

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