Comment 13 for bug 1677924

Hi

Thanks for the update

---
Thanks,
Noam Rathaus

On Apr 21, 2017 04:15, "Tyler Hicks" <email address hidden> wrote:

> As a note to any backporters, the original fix for this bug should
> include the following change as well:
>
> https://code.launchpad.net/~tyhicks/lightdm/guest-dir-
> perms/+merge/322906
>
> It is technically optional but definitely recommended.
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1677924
>
> Title:
> Local privilege escalation via guest user login
>
> Status in Light Display Manager:
> Fix Released
> Status in Light Display Manager 1.18 series:
> Fix Released
> Status in Light Display Manager 1.20 series:
> Fix Released
> Status in Light Display Manager 1.22 series:
> Fix Released
> Status in lightdm package in Ubuntu:
> Fix Released
> Status in lightdm source package in Xenial:
> Fix Released
> Status in lightdm source package in Yakkety:
> Fix Released
> Status in lightdm source package in Zesty:
> Fix Released
>
> Bug description:
> It was discovered that a local attacker could watch for lightdm's
> guest-account script to create a /tmp/guest-XXXXXX file and then quickly
> create
> the lowercase representation of the guest user's home directory before
> lightdm
> could. This allowed the attacker to have control of the guest user's home
> directory and, subsequently, gain control of an arbitrary directory in
> the
> filesystem which could lead to privilege escalation.
>
> To manage notifications about this bug go to:
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>