Re: LXC: CVE-2017-5985: lxc-user-nic didn't verify network namespace ownership

[Stiepan <stie@itk.swiss>]

I don't know whether that is the same bug, or a related one, but on Debian8 using LXC from jessie-backports, setting 
the default route in a container affects the host - namely, from an unpriv. container, setting the route sets the 
host's route as well.
lxc-info --version outputs 2.0.6 and no update is currently available (on Debian).

Stiepan



-------- Original Message --------
Subject: [oss-security] LXC: CVE-2017-5985: lxc-user-nic didn't verify network namespace ownership
Local Time: 9 March 2017 5:54 PM
UTC Time: 9 March 2017 16:55
From: tyhicks () canonical com
To: oss-security () lists openwall com
Stéphane Graber <stgraber () ubuntu com>

Jann Horn discovered that the lxc-user-nic program could be tricked into
operating on a network namespace over which the caller did not hold
privilege.

The behavior didn't follow what was documented in the lxc-user-nic(1)
man page:

It ensures that the calling user is privileged over the network
namespace to which the interface will be attached.

This issue is CVE-2017-5985.

https://lists.linuxcontainers.org/pipermail/lxc-users/2017-March/012925.html
https://launchpad.net/bugs/1654676
https://github.com/lxc/lxc/commit/16af238036a5464ae8f2420ed3af214f0de875f9

Tyler