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[FLSA-2005:152771] Updated pam packages fix security issue
From: Marc Deslauriers <marcdeslauriers () videotron ca>
Date: Wed, 18 May 2005 16:49:20 -0400

               Fedora Legacy Update Advisory

Synopsis:          Updated pam packages fix security issue
Advisory ID:       FLSA:152771
Issue date:        2005-05-18
Product:           Red Hat Linux
Keywords:          Bugfix
CVE Names:         CAN-2003-0388

1. Topic:

Updated pam packages that fix a security vulnerability are now

PAM (Pluggable Authentication Modules) is a system security tool that
allows system administrators to set an authentication policy without
having to recompile programs that handle authentication.

2. Relevant releases/architectures:

Red Hat Linux 7.3 - i386
Red Hat Linux 9 - i386

3. Problem description:

These updates fix a potential security problem present in the pam_wheel
module. These updates correct a bug in the pam_lastlog module which
prevented it from properly manipulating the /var/log/lastlog entry for
users with very high user IDs.

The pam_wheel module is used to restrict access to a particular service
based on group membership. If the pam_wheel module was used with the
"trust" option enabled, but without the "use_uid" option, any local user
would be able to spoof the username returned by getlogin(). The user
could therefore gain access to a superuser account without supplying a
password. The Common Vulnerabilities and Exposures project
(cve.mitre.org) has assigned the name CAN-2003-0388 to this issue.

When manipulating the entry in /var/log/lastlog, which corresponds to a
given user, the pam_lastlog module calculates the location of the entry
by multiplying the UID and the length of an entry in the file. On some
systems, the result of this calculation would mistakenly be truncated to
32 bits for users with sufficiently high UIDs.

All users of pam should upgrade to these updated packages, which resolve
these issues.

4. Solution:

Before applying this update, make sure all previously released errata
relevant to your system have been applied.

To update all RPMs for your particular architecture, run:

rpm -Fvh [filenames]

where [filenames] is a list of the RPMs you wish to upgrade.  Only those
RPMs which are currently installed will be updated.  Those RPMs which
are not installed but included in the list will not be updated.  Note
that you can also use wildcards (*.rpm) if your current directory *only*
contains the desired RPMs.

Please note that this update is also available via yum and apt.  Many
people find this an easier way to apply updates.  To use yum issue:

yum update

or to use apt:

apt-get update; apt-get upgrade

This will start an interactive process that will result in the
appropriate RPMs being upgraded on your system.  This assumes that you
have yum or apt-get configured for obtaining Fedora Legacy content.
Please visit http://www.fedoralegacy.org/docs for directions on how to
configure yum and apt-get.

5. Bug IDs fixed:


6. RPMs required:

Red Hat Linux 7.3:


Red Hat Linux 9:



7. Verification:

SHA1 sum                                 Package Name


These packages are GPG signed by Fedora Legacy for security.  Our key is
available from http://www.fedoralegacy.org/about/security.php

You can verify each package with the following command:

    rpm --checksig -v <filename>

If you only wish to verify that each package has not been corrupted or
tampered with, examine only the sha1sum with the following command:

    sha1sum <filename>

8. References:


9. Contact:

The Fedora Legacy security contact is <secnotice () fedoralegacy org>. More
project details at http://www.fedoralegacy.org


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