I can hack and access the lock screen without any given password through the shortcut keys of Alt+Shift.

[Jarurote Tippayachai]

With frequently pressing the shortcut keys of Alt+Shift, we can hack and access through the lock screen without any given password.

See also
https://www.youtube.com/watch?v=s968NpIpdiQ

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: xorg 1:7.7+13ubuntu3
ProcVersionSignature: Ubuntu 4.4.0-31.50-generic 4.4.13
Uname: Linux 4.4.0-31-generic x86_64
.tmp.unity_support_test.0:

ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: compiz
CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0'
CompositorUnredirectFSW: true
Date: Fri Aug 5 13:11:19 2016
DistUpgraded: 2016-07-29 16:02:34,562 ERROR got error from PostInstallScript ./xorg_fix_proprietary.py (Failed to execute child process "./xorg_fix_proprietary.py" (No such file or directory))
DistroCodename: xenial
DistroVariant: ubuntu
GraphicsCard:
 Intel Corporation Xeon E3-1200 v2/3rd Gen Core processor Graphics Controller [8086:0152] (rev 09) (prog-if 00 [VGA controller])
   Subsystem: Hewlett-Packard Company Xeon E3-1200 v2/3rd Gen Core processor Graphics Controller [103c:18dd]
InstallationDate: Installed on 2015-11-12 (266 days ago)
InstallationMedia: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
MachineType: Hewlett-Packard HP Compaq Pro 4300 AiO 20 PC
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-31-generic root=UUID=0dd8d4f8-3576-45ac-af4a-b79a43b4b17b ro quiet splash vt.handoff=7
SourcePackage: xorg
Symptom: display
UpgradeStatus: Upgraded to xenial on 2016-07-29 (6 days ago)
dmi.bios.date: 01/30/2013
dmi.bios.vendor: AMI
dmi.bios.version: 8.08
dmi.board.asset.tag: 3CR3200N71
dmi.board.name: 18DD
dmi.board.vendor: PEGATRON CORPORATION
dmi.board.version: 1.02
dmi.chassis.asset.tag: 3CR3200N71
dmi.chassis.type: 3
dmi.chassis.vendor: Hewlett-Packard
dmi.modalias: dmi:bvnAMI:bvr8.08:bd01/30/2013:svnHewlett-Packard:pnHPCompaqPro4300AiO20PC:pvr1.00:rvnPEGATRONCORPORATION:rn18DD:rvr1.02:cvnHewlett-Packard:ct3:cvr:
dmi.product.name: HP Compaq Pro 4300 AiO 20 PC
dmi.product.version: 1.00
dmi.sys.vendor: Hewlett-Packard
version.compiz: compiz 1:0.9.12.2+16.04.20160714-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.67-1ubuntu0.16.04.1
version.libgl1-mesa-dri: libgl1-mesa-dri 11.2.0-1ubuntu2.1
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 11.2.0-1ubuntu2.1
version.xserver-xorg-core: xserver-xorg-core 2:1.18.3-1ubuntu2.3
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.10.1-1ubuntu2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.7.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20160325-1ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.12-1build2
xserver.bootTime: Fri Aug 5 09:34:43 2016
xserver.configfile: default
xserver.errors:

xserver.logfile: /var/log/Xorg.0.log
xserver.outputs:
 product id 16930
 vendor HWP
xserver.version: 2:1.18.3-1ubuntu2.3

[Jarurote Tippayachai (jarurote)]

I can hack and access the lock screen without any given password with Alt+Shift shortcut keys as shown in this links:

https://www.youtube.com/watch?v=s968NpIpdiQ

[Paul White (paulw2u)]

Obviously not an xorg problem.

Assigning to Ubuntu pending reassignment to the correct package.

[Jarurote Tippayachai (jarurote)]

I have forgot to say that I cannot switch the language between Thai and English with Alt+Shift shortcut keys on the lock screen after upgrading my Ubuntu OS from 14.04 LTS to 16.04 LTS, but it is also appeared the crash screen as shown in YouTube.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.