No .ICEauthority file at all in i686 trusty's Kubuntu 14.04.1, Lubuntu 14.04, 14.04.1, and in amd64 Kubuntu 14.04.

[moko138]

No .ICEauthority file at all
in i686 trusty's Kubuntu 14.04.1, Lubuntu 14.04 and 14.04.1,
nor in amd64 Kubuntu 14.04.

I detected four cases in installed trusties : there is no .ICEauthority in /home/main_user. Nevertheless users can log in. You can see the phenomenon as soon as the live usb has been burned. You don't even need to install.

I already could reproduce it for
Lubuntu-14.04-desktop-i386.iso, b0d1c58c8515ab40382d01f59655ba85
==============

First case (first user) :
Lubuntu iso unknown,
burned with lili usb creator.
lsb_release -d Description:
(L)Ubuntu 14.04.1 LTS
uname -r Linux XXXX 3.13.0-33-generic
cat /proc/cpuinfo
dual core processor: Intel Atom N270

Second case (same user) :
other iso but same user and same hardware as above.
Lubuntu-14.04-desktop-i386.iso, b0d1c58c8515ab40382d01f59655ba85
burned with lili usb creator.
With updates, according to the kernel.
uname -a Linux XXXX 3.13.0-33-generic #58-Ubuntu SMP Tue Jul 29 16:47:17 UTC 2014 i686 i686 i686 GNU/Linux

Third case; second user :
Kubuntu iso unknown.
lsb_release -d Description: (K)Ubuntu 14.04.1 LTS
uname -a Linux YYYY 3.13.0-32-generic #57-Ubuntu SMP Tue Jul 15 03:51:12 UTC 2014
Processor: AMD Athlon II X2 250

==============
Fourth case; third user (me)
Kubuntu-14.04-desktop-amd64.iso, aefdc97d26e51066f5b50d36c5d4218c
From cdimage.ubuntu.com/kubuntu/releases/14.04/release/kubuntu-14.04-desktop-amd64.iso
  Beginning with :
amd64 AMD Athlon dual core 5050e
and using a persistent live lsb_release -d Description: (X)Ubuntu 14.04 LTS
kernel 3.13.0-24-generic (...) i686,
  I took again my micro-SD card and washed it up with
sudo dd if=/dev/zero of=/dev/sdf bs=512 count=4096
Then created, using gparted, a msdos partitions table.
Then i tried to burn it with persistency, using usb-creator-gtk 0.2.23, of my persistent live Xubuntu 14.04 : FAILURE
  Using gparted, i created a new fat32 partition, aligned on cylinders.
New try to burn, without persistency : ok

  Plugged to another pc, with
Intel core 2duo P8600 :
            NO .ICEauthority again.

==============
I (third user) had reproduced the second case with this process :
I took a micro-SD card and washed it up with
sudo dd if=/dev/zero of=/dev/sdx bs=512 count=4000
Then i burned it with usb-creator-gtk 0.2.23, of a Xubuntu 12.04.5
(uname -a
Linux ZZZZ 3.2.0-67-generic #101-Ubuntu SMP Tue Jul 15 17:45:51 UTC 2014 i686 i686 i386 GNU/Linux)
and an Intel Atom N270 processor.
Then I plugged it in another pc, with an amd64 AMD Athlon dual core processor 5050e.
And so it was : no .ICEauthority, but i could boot and reboot the live session.

===============
More details (dpkg --get-selections, cat .bash_history and so on)
on http://forum.ubuntu-fr.org/viewtopic.php?pid=17711471#p17711471 (for french speaking).

[Marc Deslauriers (mdeslaur)]

Thanks for taking the time to report this bug and helping to make Ubuntu better. We appreciate the difficulties you are facing, but this appears to be a "regular" (non-security) bug. I have unmarked it as a security issue since this bug does not show evidence of allowing attackers to cross privilege boundaries nor directly cause loss of data/privacy. Please feel free to report any other bugs you may find.

[moko138 (tfjb321)]

   Thanks, Marc, for answering !
Well, I understood :
"It's not a bug, it's a feature !"
  Sorry ! et Merci !
moko138
--------------------------------------------
En date de : Mar 19.8.14, Marc Deslauriers <email address hidden> a écrit :
 Objet: [Bug 1357560] Re: No .ICEauthority file at all in i686 trusty's Kubuntu 14.04.1, Lubuntu 14.04, 14.04.1, and in amd64 Kubuntu 14.04.
 À: <email address hidden>
 Date: Mardi 19 août 2014, 17h18

 Thanks for taking the time to report
 this bug and helping to make Ubuntu
 better. We appreciate the difficulties you are facing, but
 this appears
 to be a "regular" (non-security) bug.  I have unmarked
 it as a security
 issue since this bug does not show evidence of allowing
 attackers to
 cross privilege boundaries nor directly cause loss of
 data/privacy.
 Please feel free to report any other bugs you may find.

 ** Information type changed from Public Security to Public

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 Title:
   No .ICEauthority file at all in i686 trusty's Kubuntu
 14.04.1, Lubuntu
   14.04, 14.04.1, and in amd64 Kubuntu 14.04.

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