What steps to take to mitigate newly discovered CVE-2016-5195 privilege-escalation?

[howefield]

...and it seems to have fixed the issue.

Cool, well done on sussing it out.

Bear in mind that you'll likely have more upgrading to do next April as 12.04 hits the end of the road

[RichardET]

uname -r
4.4.0-45-generic

Presumably this kernel does not have the bug?

[howefield]

Presumably this kernel does not have the bug?

Sort of.. I believe you need to have 4.4.0-45.66 to be patched. What's the output of..

apt-cache policy linux-image-4.4.0-45-generic

apt-cache policy linux-image-4.4.0-45-generic 
linux-image-4.4.0-45-generic:
  Installed: 4.4.0-45.66
  Candidate: 4.4.0-45.66
  Version table:
 *** 4.4.0-45.66 500
        500 http://gb.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages
        500 http://security.ubuntu.com/ubuntu xenial-security/main amd64 Packages
        100 /var/lib/dpkg/status

https://people.canonical.com/~ubuntu...2016-5195.html

[RichardET]

Installed: 4.4.0-45.66
Candidate: 4.4.0-45.66
Version table:
*** 4.4.0-45.66 500
500 http://us.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages
500 http://security.ubuntu.com/ubuntu xenial-security/main amd64 Packages
100 /var/lib/dpkg/status


Thus I guess I have the correct updates installed.

[howefield]

...Thus I guess I have the correct updates installed.

Yep, jobs a good 'un.