mozroots fails to import certificates

[gohanman]

Description: Ubuntu 14.04.4 LTS
Release: 14.04

mono-devel:
  Installed: 3.2.8+dfsg-4ubuntu1.1
  Candidate: 3.2.8+dfsg-4ubuntu1.1
  Version table:
 *** 3.2.8+dfsg-4ubuntu1.1 0
        500 http://us.archive.ubuntu.com/ubuntu/ trusty-updates/main amd64 Packages
        500 http://security.ubuntu.com/ubuntu/ trusty-security/main amd64 Packages
        100 /var/lib/dpkg/status
     3.2.8+dfsg-4ubuntu1 0
        500 http://us.archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages

I'm trying to use mozroots to import certificates. It's not succeeding.

$ sudo mozroots --import --sync --machine
Mozilla Roots Importer - version 3.2.8.0
Download and import trusted root certificates from Mozilla's MXR.
Copyright 2002, 2003 Motus Technologies. Copyright 2004-2008 Novell. BSD licensed.

Downloading from 'http://mxr.mozilla.org/seamonkey/source/security/nss/lib/ckfw/builtins/certdata.txt?raw=1'...
Couldn't retrieve the file using the supplied information.

The lack of proper certificates means basically everything related to using nuget fails, too, and the mono development environment isn't terribly useful.

Steps to reproduce:
$ sudo apt-get install mono-devel
$ sudo mozroots --import --sync --machine