*** This bug is a security vulnerability ***

You have been subscribed to a public security bug by Jamie Strandboge 
(jdstrand):

Binary package hint: libpam-keyring

This is on up-to-date Gutsy:

libpam-keyring doesn't work correctly when set-up together with gdm's
autologin feature.

As expected, GDM logins automatically the correct user. However libpam-
keyring fails to retrieve the user's password (probably because it
wasn't entered) and instead displays a dialog box asking for it, which
defeats the purpose of the plugin. Instead, if the password isn't
available it should just do nothing (perhaps log a message somewhere)
and allow the normal keyring unlocking to work (eg, let Network Manager
ask for the password when it needs it). This locks the loading process,
which is very annoying.

Also, the dialog where libpam-keyring asks for the password does NOT
mask the entered password (eg, with asterisks), making it visible on the
screen. That's why I'm marking this as a (minor) security vulnerability.

Note: of course this can be worked-around by simply disabling the plugin
in /etc/pam.d/gdm-autologin (and it doesn't put itself there), but it's
still buggy behavior.

It's likely that libpam cannot actually retrieve the password on
autologins (I assume GDM just "su -"s into the username, so it doesn't
actually know the password), in which case this should be attached as a
"wishlist" bug for GDM or gnome-keyring. For instance, gnome-keyring
might allow itself to be unlocked by the "root" user as an optional,
lower-security feature.

Here's my config:

$ cat /etc/pam.d/gdm-autologin
#%PAM-1.0
auth    requisite       pam_nologin.so
auth    required        pam_env.so readenv=1
auth    required        pam_env.so readenv=1 envfile=/etc/default/locale
auth    required        pam_permit.so
auth    optional        pam_keyring.so try_first_pass
@include common-account
session required        pam_limits.so
session optional        pam_keyring.so
@include common-session
@include common-password

** Affects: gnome-keyring
     Importance: Unknown
         Status: Invalid

** Affects: gdm (Ubuntu)
     Importance: Medium
         Status: Confirmed

** Affects: pam-keyring (Ubuntu)
     Importance: Undecided
     Assignee: Laurent Bigonville (bigon)
         Status: Won't Fix

** Affects: gdm (Baltix)
     Importance: Undecided
         Status: New

-- 
libpam-keyring broken on autologins
https://bugs.launchpad.net/bugs/137247
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